I-94 card

My wife is a H4 Visa holder. She recently visited China and got a new I-94 card.
By mistake, she forgot to fill out the I-94 card number on the new I-94 card.

Suppose, the I-94 card should have a constant number. Now the I-94 card has different number than before. What should we do now?

Could we just fill the previous I-94 card number on the new I-94 card?
Do we need to go to the local INS and ask INS officer to correct this mistake?


Thanks.


fishlet