We purchased 4 Hershey Park tickets just before COVID hit and Hershey Park had to close. May we still use these tickets for this year's visit?

Us too...expire june 30th

You should be able to use them until 6/30.

Only customer service will be able to assist you appropriately

Talk to Hershey's customer service. They should be able to reissue a ticket for you so you may use during this summer.