yesterday I order three donation for my panel and by mistake I use the wrong email what can I do to reverse this

Hi everybody: I Have a Mag 250 and I would like use the RCA cables that came with it, and use it on my old TV that I have in PR. My TV is not an HD, thats why I need to use the RCA. Do I have to do any changed in the set up.....I try NTSC 480i and dont work....any other changed I have to do.