If there is an advertisement at startup please see: https://github.com/2dust/v2rayNG/issues/930

Project address: https://github.com/2dust/v2rayNG
The current client uses Xray-core (https://github.com/XTLS/Xray-core)
Please download the v2fly-core client: https://play.google.com/store/apps/details?id=com.v2ray.v2fly