MIssing credit

So travelstart called me but I couldn't answer as I had my hands full of dough. They sent a email saying they can't find my credit, after I spoke to a lady and she even checked flights for me. I told her to put it in credit let me get my dates sorted out and then book. Now I found out there is no credit so explain to me where is it and why was it not recorded as the lady who helped me said she has put it on credit and she explained to me how to find it. Now its not there. So what now?