I am a blogger and write about Electronic gadgets and power banks too! Here is my small blog PowerBankTalk
Responder a: Slow charging using the original charger and wall socketThere might be loose connection issue in your phones charger adapter may be replacing it will solve this but charge with same configuration charger first !
Responder a: How to fix loose usb port of Xiaomi power bankFirst of all, you need to check the power bank for its originality here is my post about genuine vs fake xiaomi power banks and how to identify one. Then you can try to put some kind of rubber of padding of paper to make it less movable thus it will be partially fixed. Though there is no permanent fix for this. You can buy new power banks from our best power bank review list which are ranked as per performance and portability!