My f15 does not support fast charging with MI 4i 20000 mah 33 watt powerbankAll cable, phone , powerbank are ok

My samsung f15 does not charging with mi 4i 20000 mah powerbank with type c to c.WHAT CAN I DO TO FIX THE PROBLEM...

One ui 7 update for f15 will be harmful be like green line issues, fast charging problem,many types of screen problem. Because we are already showing in this app many m15,f34,etc. Users notify those problems. Those problems are also be happened in f1...