What he said.

What if my Form I-94 has been lost, stolen, mutilated, or
destroyed?
If you need to replace a paper Form I-94 that was issued to you
upon admission to the United States or that was issued to you by
USCIS, you must apply for a replacement Form I-94 with USCIS by
using Form I-102.
If you entered the United States after I-94 automation (April 30,
2013) and you were not issued a paper I-94, your I-94 record of
admission can be obtained by visiting www.cbp.gov/I94.

Good luck!