Not received gift

Joined on the offer for free tv or money off account, went with tv and now after a month and the time to get out of contact passed they are now saying I’m not eligible, no more detail then that but next person I speak with saying stock issues and I am eligible then next person not eligible. Left hand does not know what right hand is doing but have the call transcript with the tv being offered and accepted so I’m going to raise a complaint with Communications Ombudsman as this is false advertising and poor service. Why offer if you have no intention to follow up.  Very poor service for new customers