I can get help .. you can put as mandatory field http://prntscr.com/ho0zvj

if you want to knoqw about custom fields you better search on osclass forums

There is more then enough information

I ask only if possible to also put that as a mandatory field being that it is part of the Osclass pay plugin

you ask about pay plugin and post it in veronika forums

Totally dont understand what you want

spiegati meglio davide

jij ook jochie