Originally Posted by
plunet
What you might be facing is that due to the difficulty for mainland Chinese tourists to travel at the moment, although Unionpay should be accepted at some retailers in the US, due to the lack of use things have broken for some retailers? If you really want to test it in the US I would suggest going to a significant Chinatown area and try some transactions there.
Another possibility is to visit the nearest major outlet mall, as these are very popular with international tourists and thus are likely to have substantial experience with Unionpay.