Don't you have Chinese tips? If the POS machine shows that the card swiping is unsuccessful, one possibility is that there is something wrong with the magnetic stripe or chip of the card itself. You can take your credit card and valid certificate to the counter of any CCB outlet nearby for magnetic stripe detection. Another possibility is that the network communication failed, so you can try to use another POS. Or the landlord can look at the credit card he holds. If it is a VISA or MASTER single-label credit card, these cards do not support UnionPay merchants.