I honestly don’t know as you didn’t mention the number, but it would be unusual for avast 3rd party support to recommend using another product. There have been some bad experiences with 3rd party support but not in this way, some have had them try to sell them a support service indicating the problem isn’t covered in the free support.
Yes, nothing to do with avast, and I believe that was the problem, they don’t appear to have any experience of avast so would palm you off on another VA in the hope that that resolves the problem.