Appstore purchase issue(country region and financial issues)

I changed my itune country region to china mainland but myself was in US for payment in an app, but after I finished payment and it said successful, I just realized that my chinese id just expired and I was using wechat, and now it said that there was a pending payment and I cannot change my region to US and I cannot update any apps, and because I bind my appstore with wechat payment I cannot import a new id and I cannot unbind because of this pending payment, the only payment method I have is wechat, do you guys have any ideas to help me fix this, (I have enough money in wechat wallet to pay the overdue thing) D: