Be careful with WeChat.
I did manage to redeem something, after reading here in reviews that you should use the PIN and not the code, but it is a discount card not not wechat pay top-up. My 100cny card can be used for purchases above 100.1cny. I can use it for paying for utilities in China (which of course I don't have) or adding coins to QQ, which, again, I don't have.