https://docs.strapi.io/developer-docs/latest/update-migration-guides/migration-guides/v4/migration-guide-4.2.x-to-4.3.x.html After running strapi (postgres db) migrated to 4.3.x I've a key violation error: insert into "strapi_core_store_settings" ("environment", "key", "tag", "type", "value") values ($1, $2, $3, $4, $5) returning "id" - duplicate key value violates unique constraint "strapi_core_store_settings_pkey" to make it short the fix is to update strapi_core_store_settings_id_seq with the following sql script SELECT setval('strapi_core_store_settings_id_seq', COALESCE((select max(id) from strapi_core_store_settings), 0), true)