Help! Gcash deducted my amount

Nag rebook po ako ng flight with cebupacific and I was redirected to the Gcash payment site. Upon confirmation of payment and pa redirect po back sa cebupac website nag crash ang website. Upon checking, wala po changes sa flight pero deducted na ang amount. Upon asking the chatbox of cebpac, ang sabi wala daw po sila natanggap na payment and changes in booking but will forward the issue. What should I do?