diff --git a/backend/src/professionals/professionals.service.ts b/backend/src/professionals/professionals.service.ts
index 6e67701..5d60bcf 100644
--- a/backend/src/professionals/professionals.service.ts
+++ b/backend/src/professionals/professionals.service.ts
@@ -25,7 +25,8 @@ export class ProfessionalsService {
   }
 
   async findById(id: string) {
-    const prof = await this.prisma.professionals.findUnique({
+    // Accept either the professional UUID or the user_id (legacy Flutter behavior)
+    let prof = await this.prisma.professionals.findUnique({
       where: { id },
       include: {
         users: { select: { id: true, name: true, picture: true, city: true } },
@@ -34,6 +35,17 @@ export class ProfessionalsService {
         payment_methods: true,
       },
     });
+    if (!prof) {
+      prof = await this.prisma.professionals.findUnique({
+        where: { user_id: id },
+        include: {
+          users: { select: { id: true, name: true, picture: true, city: true } },
+          schedules: { orderBy: { day_of_week: 'asc' } },
+          specializations: true,
+          payment_methods: true,
+        },
+      });
+    }
     if (!prof) throw new NotFoundException('Profesional no encontrado');
     return prof;
   }
diff --git a/backend/src/services/services.service.ts b/backend/src/services/services.service.ts
index 706d9c8..120e9e8 100644
--- a/backend/src/services/services.service.ts
+++ b/backend/src/services/services.service.ts
@@ -21,12 +21,14 @@ export class ServicesService {
     longitude?: number;
     location_preference?: 'office' | 'delivery';
   }) {
-    const prof = await this.prisma.professionals.findUnique({ where: { id: data.professional_id } });
+    // Accept either professional UUID or user_id (legacy Flutter behavior)
+    let prof = await this.prisma.professionals.findUnique({ where: { id: data.professional_id } });
+    if (!prof) prof = await this.prisma.professionals.findUnique({ where: { user_id: data.professional_id } });
     if (!prof || !prof.is_active) throw new BadRequestException('Profesional no disponible');
 
     return this.prisma.services.create({
       data: {
-        professional_id: data.professional_id,
+        professional_id: prof.id,
         user_id: data.user_id,
         day: new Date(data.day),
         description: data.description,