I fast, memorize Quran, seek knowledge, morning and evening adhkar, qiyamul layl, duha, dhikr all day, forgive others, give charity, do acts of kindness for my mother, play withsiblings, sunnah prayers,EVEN STILL almost everyday I watch porn and touch myself what's the matter with me whats the cure

Repentance with sincerity is accepted however many times it is broken. Cut off what leads to it, especially being alone with your phone, lower your gaze, fast, and hasten marriage if you can. Alhamdulilah that there is alot of goodness in your life, so do not let 1 sin bring you down like this, so try to improve gradually and focus on getting married when you are able to