diff --git a/backend/src/.jest-cache/haste-map-60cab15b743c6776f41d29bcac696b99-0ca4a1d6e3dfec1d63b61b0119442391-1908b04cd11e739233ee8977de00dc57 b/backend/src/.jest-cache/haste-map-60cab15b743c6776f41d29bcac696b99-0ca4a1d6e3dfec1d63b61b0119442391-1908b04cd11e739233ee8977de00dc57
index 66badb7..abb55eb 100644
Binary files a/backend/src/.jest-cache/haste-map-60cab15b743c6776f41d29bcac696b99-0ca4a1d6e3dfec1d63b61b0119442391-1908b04cd11e739233ee8977de00dc57 and b/backend/src/.jest-cache/haste-map-60cab15b743c6776f41d29bcac696b99-0ca4a1d6e3dfec1d63b61b0119442391-1908b04cd11e739233ee8977de00dc57 differ
diff --git a/frontend/app/(admin)/admin/doc-control/reference/disciplines/page.tsx b/frontend/app/(admin)/admin/doc-control/reference/disciplines/page.tsx
index 3f9dff9..76d5990 100644
--- a/frontend/app/(admin)/admin/doc-control/reference/disciplines/page.tsx
+++ b/frontend/app/(admin)/admin/doc-control/reference/disciplines/page.tsx
@@ -81,12 +81,12 @@ export default function DisciplinesPage() {
         queryKey={['disciplines', selectedContractId ?? 'all']}
         fetchFn={async () => {
           const items = await masterDataService.getDisciplines(selectedContractId ? selectedContractId : undefined);
-          // ADR-019: Map contractId INT → contract UUID for edit mode select matching
+          // ADR-019: Map contract.publicId UUID for edit mode select matching
           return items.map((item) => {
-            const rec = item as Discipline & { contract?: { id?: number; uuid?: string }; contractId?: number | string };
+            const rec = item as Discipline & { contract?: { publicId?: string }; contractId?: number | string };
             return {
               ...item,
-              contractId: rec.contract?.id || rec.contract?.uuid || String(rec.contractId),
+              contractId: rec.contract?.publicId || (rec.contractId ? String(rec.contractId) : null),
             } as Discipline;
           });
         }}
diff --git a/frontend/app/(admin)/admin/doc-control/reference/rfa-types/page.tsx b/frontend/app/(admin)/admin/doc-control/reference/rfa-types/page.tsx
index dc6e1dc..da2fd67 100644
--- a/frontend/app/(admin)/admin/doc-control/reference/rfa-types/page.tsx
+++ b/frontend/app/(admin)/admin/doc-control/reference/rfa-types/page.tsx
@@ -84,12 +84,12 @@ export default function RfaTypesPage() {
         queryKey={['rfa-types', selectedContractId ?? 'all']}
         fetchFn={async () => {
           const items = await masterDataService.getRfaTypes(selectedContractId ? selectedContractId : undefined);
-          // ADR-019: Map contractId INT → contract UUID for edit mode select matching
+          // ADR-019: Map contract.publicId UUID for edit mode select matching
           return items.map((item) => {
-            const rec = item as RfaType & { contract?: { id?: number | string; uuid?: string }; contract_id?: number | string };
+            const rec = item as RfaType & { contract?: { publicId?: string }; contractId?: number | string };
             return {
               ...item,
-              contractId: rec.contract?.id || rec.contract?.uuid || (rec.contract_id ? String(rec.contract_id) : null),
+              contractId: rec.contract?.publicId || (rec.contractId ? String(rec.contractId) : null),
             } as RfaType;
           });
         }}
diff --git a/frontend/components/numbering/template-editor.tsx b/frontend/components/numbering/template-editor.tsx
index 814e630..41e7756 100644
--- a/frontend/components/numbering/template-editor.tsx
+++ b/frontend/components/numbering/template-editor.tsx
@@ -46,8 +46,8 @@ export function TemplateEditor({
   onCancel,
 }: TemplateEditorProps) {
   const [format, setFormat] = useState(template?.formatTemplate || '');
-  const [typeId, setTypeId] = useState<string>(template?.correspondenceTypeId?.toString() || '');
-  const [disciplineId, setDisciplineId] = useState<string>(template?.disciplineId?.toString() || '0');
+  const [typeId, setTypeId] = useState<string>(template?.correspondenceTypeId ? String(template.correspondenceTypeId) : '');
+  const [disciplineId, setDisciplineId] = useState<string>(template?.disciplineId ? String(template.disciplineId) : '0');
   const [reset, setReset] = useState(template?.resetSequenceYearly ?? true);
 
   const [preview, setPreview] = useState('');
@@ -64,7 +64,7 @@ export function TemplateEditor({
       // Dynamic context based on selection (optional visual enhancement)
       if (v.key === '{TYPE}' && typeId) {
         const t = correspondenceTypes.find(
-          (ct) => ct.id?.toString() === typeId
+          (ct) => String(ct.publicId) === typeId
         );
         if (t) replacement = t.typeCode;
       }
@@ -120,7 +120,7 @@ export function TemplateEditor({
                 <SelectItem value="__default__">Default (All Types)</SelectItem>
                 {correspondenceTypes.map((type) => {
                   return (
-                    <SelectItem key={type.publicId} value={type.publicId.toString()}>
+                    <SelectItem key={type.publicId} value={String(type.publicId)}>
                       {type.typeCode} - {type.typeName}
                     </SelectItem>
                   );
@@ -142,7 +142,7 @@ export function TemplateEditor({
                 <SelectContent>
                   <SelectItem value="0">All Disciplines</SelectItem>
                   {disciplines.map((d) => (
-                    <SelectItem key={d.publicId} value={d.publicId.toString()}>
+                    <SelectItem key={d.publicId} value={String(d.publicId)}>
                       {d.disciplineCode} - {d.codeNameEn || d.codeNameTh}
                     </SelectItem>
                   ))}
diff --git a/frontend/components/rfas/form.tsx b/frontend/components/rfas/form.tsx
index 76b6a91..1a544f1 100644
--- a/frontend/components/rfas/form.tsx
+++ b/frontend/components/rfas/form.tsx
@@ -25,7 +25,7 @@ import { Contract } from '@/types/contract';
 const rfaSchema = z.object({
   projectId: z.string().min(1, 'Project is required'), // ADR-019: UUID
   contractId: z.string().min(1, 'Contract is required'),
-  disciplineId: z.number({ message: 'Discipline is required' }).min(1, 'Discipline is required'),
+  disciplineId: z.union([z.string().min(1, 'Discipline is required'), z.number().min(1, 'Discipline is required')]),
   rfaTypeId: z.string().min(1, 'Type is required'), // ADR-019: UUID
   subject: z.string().min(5, 'Subject must be at least 5 characters'),
   description: z.string().optional(),
@@ -165,7 +165,7 @@ export function RFAForm() {
     defaultValues: {
       projectId: '',
       contractId: '',
-      disciplineId: 0,
+      disciplineId: '',
       rfaTypeId: '',
       subject: '',
       description: '',
@@ -366,7 +366,7 @@ export function RFAForm() {
               onValueChange={(val) => {
                 setValue('projectId', val);
                 setValue('contractId', '');
-                setValue('disciplineId', 0);
+                setValue('disciplineId', '');
                 setValue('rfaTypeId', '');
                 setValue('shopDrawingRevisionIds', []);
                 setValue('asBuiltDrawingRevisionIds', []);
@@ -402,7 +402,7 @@ export function RFAForm() {
                 value={selectedContractId || undefined}
                 onValueChange={(val) => {
                   setValue('contractId', val);
-                  setValue('disciplineId', 0);
+                  setValue('disciplineId', '');
                   setValue('rfaTypeId', '');
                   setValue('shopDrawingRevisionIds', []);
                   setValue('asBuiltDrawingRevisionIds', []);
@@ -434,8 +434,8 @@ export function RFAForm() {
             <div>
               <Label>Discipline *</Label>
               <Select
-                value={selectedDisciplineId > 0 ? String(selectedDisciplineId) : undefined}
-                onValueChange={(val) => setValue('disciplineId', Number(val))}
+                value={selectedDisciplineId ? String(selectedDisciplineId) : undefined}
+                onValueChange={(val) => setValue('disciplineId', val)}
                 disabled={!selectedContractId || isLoadingDisciplines}
               >
                 <SelectTrigger>