However, it doesn't matter if it is different. When we do this for our relatives, we always take pens with us.

What matters is the signature on the back of the card. Theoretically, it should be consistent with the signature when signing the bill. The specific application depends on the cashier's professional quality and company requirements.

When I swiped my card in Suning, I was asked to re-sign it twice because the signatures on the back of the card were inconsistent, and I had to take out my ID card for verification. (mainly because I didn't sign my name on the back)