The IRS has been pushing out notices since last Fall explaining that the notices, such as "we need your return" are automated and would be ignored, because they also understand it is their own backlog that is the bottleneck. So, now that the return has been sent multiple times, I would stop doing anything and wait until something else happens, such as, they find and process that return.

Are you signed up for the e-newsletters that are the method for getting the notices?

Government e-newsletter signup

Such as:

https://public.govdelivery.com/accounts/USIRS/subscriber/new?preferences=true

For a bunch of portals. You are likely going to want IRS, Payroll, SBA, DOL. Here is a list from that link I provided: You get to checkmark what you want to get for notices.