It may be because the charging bank has no electricity, you can try to re-charge with the charging cable for a period of time and then try to use it. In addition, it may also be that the charging treasure itself is faulty, and it is necessary to contact the after-sales service for repair or replacement.
There is also a case where the phone or other device and the charging bank are poorly connected, and you can check whether the connection line is normal. If these methods can not solve the problem, it is recommended to contact Xiaomi customer service for help.
Xiaomi's wireless charging board cannot be used, possibly because the charging bank has no power