I bought a 12 month subscription from someone, who used to supply me with my Openbox cline no problems whatsoever, however now on IPTV his service is trash and half the channels are missing most buffer and switch to a different channel whilst not changing channels. I paid in bank transfer aswell, anything I can do to make it better ? I asked about refund and he said he won't do a refund .
Sorry to hear that you've having such a bad experience. There isn't much you can do to press someone into giving you better customer service (Unfortunately, there isn't a Better Business Bureau for IPTV resellers) but hopefully you the issues you are experiencing are temporary and the service improves back to the level that you were used to.
A lot of people are going to chime in and say "This is why you don't purchase a year long subscription" and "Only buy a month or two at a time". I don't necessarily consider that to be a rule of thumb but do make sure you feel out and completely trust your reseller before making any long term commitments