Please can I get advice on what I should be doing next, thank you in advance
You need to complete the form PE3, get it witnessed, then copied so it can be sent via email, and send it off to TEC. Your reason is the second one, (submitted representations, but did not get a notice of rejection). There is no need to put anything in the reasons box. Witnessing is free at the local county court, or costs about £10 at a solicitors. When TEC process your PE3 (Statutory Declaration), they will order the OfR and Charge Certificate to be cancelled. The process is reverted to the representations stage, so the council must pass the matter to the adjudicators for a decision.
You only have a fixed period from the date of the OfR to submit the SD, so don't tarry.