Refill card

Accidentally bought a prepaid refill cards thinking it was a gift card. It was $400 total and I was hoping I could at least use it towards my bill or towards any device on Verizon store since  I don’t have a prepaid account. Verizon is telling me there is nothing they can do. Has anyone else run into this issue? If so what did you end up doing? I’m very frustrated  I have been with Verizon over 10 years and Verizon  can’t help with this issue, even if it was  my mistake. You’d think they could somehow make it possible for me to apply it to my  account somehow since it will all even going to Verizon at the end. If anyone can help me otherwise I'm out $400 cause I have no use for these cards.