Immigration stamped wrong date on I-20

[pm1012]

I am about to submit my 485. The immigration officer stamped XXX XX 1991 on my I-20. The date I entered this country should be XXX XX 1997. He used the same stamp on my passport page but used pen to correct "1" to "7" without any initial. He didn't make any change on my I-20.

I am worrying if this will cause me problem on my 485 application. Does anyone have any opinoin on this issue.

Thanks.