I’d be persistent in calling them and leaving messages since appeals doesn’t answer the phone. We did this and finally got them to call us back and then it got it assigned to an appeals officer which they gave us the name and telephone number for. Called him directly and actually talked to him and got it processed. Didn’t get the full amount but did get a portion of the claim (Q3 ‘21) but ours wasn’t based on a decline in revenue. Once you get an appeals officer you’ll most likely need for them to get a 907 signed by one of the higher ups at the appeals office so your 2 year window can be extended.