i sent a gift on iTunes but the person that i sent it to they cant access their email account. is there another way this person can receive the gift

Try resending it to an email account that they still have access to : Resend iTunes Gifts - Apple Support.

I Have sent some amount as a gift to my cousin, but the prolem for my cousin was that he didnt have access to the email address he was using as the apple id, so we tried to change his apple id to another email address, we have done it successfully but after that i cant resend the gift to his new email address.