diff --git a/backend/services/identity-service/prisma/migrations/20241206000000_add_device_hardware_info/migration.sql b/backend/services/identity-service/prisma/migrations/20241206000000_add_device_hardware_info/migration.sql
deleted file mode 100644
index 9f8a975c..00000000
--- a/backend/services/identity-service/prisma/migrations/20241206000000_add_device_hardware_info/migration.sql
+++ /dev/null
@@ -1,12 +0,0 @@
--- AlterTable: Add hardware info fields to user_devices
-ALTER TABLE "user_devices" ADD COLUMN "platform" VARCHAR(20);
-ALTER TABLE "user_devices" ADD COLUMN "device_model" VARCHAR(100);
-ALTER TABLE "user_devices" ADD COLUMN "os_version" VARCHAR(50);
-ALTER TABLE "user_devices" ADD COLUMN "app_version" VARCHAR(20);
-ALTER TABLE "user_devices" ADD COLUMN "screen_width" INTEGER;
-ALTER TABLE "user_devices" ADD COLUMN "screen_height" INTEGER;
-ALTER TABLE "user_devices" ADD COLUMN "locale" VARCHAR(10);
-ALTER TABLE "user_devices" ADD COLUMN "timezone" VARCHAR(50);
-
--- CreateIndex
-CREATE INDEX "idx_platform" ON "user_devices"("platform");
diff --git a/backend/services/mpc-service/prisma/migrations/20241204000000_init/migration.sql b/backend/services/mpc-service/prisma/migrations/20241204000000_init/migration.sql
index 4debe56d..57819374 100644
--- a/backend/services/mpc-service/prisma/migrations/20241204000000_init/migration.sql
+++ b/backend/services/mpc-service/prisma/migrations/20241204000000_init/migration.sql
@@ -38,8 +38,5 @@ CREATE UNIQUE INDEX "mpc_wallets_username_key" ON "mpc_wallets"("username");
 -- CreateIndex
 CREATE INDEX "idx_mw_username" ON "mpc_wallets"("username");
 
--- CreateIndex
-CREATE INDEX "idx_ms_username" ON "mpc_shares"("username");
-
--- CreateIndex
+-- CreateIndex (username is unique, so only need unique index)
 CREATE UNIQUE INDEX "uq_ms_username" ON "mpc_shares"("username");