Who issues the credential F1CC

I'm trying to get my F1CC verified after I completed my FY1, which will be EPIC/ECFMG, then sent abroad to register with another country. Who issues the F1CC? is it the Trust? Deanery? or GMC?

Has anyone had to do that in the past?

This is the question EPIC is asking for reference:Please select the medical school/institution that issued the credential.