I find it odd that I cannot find anyone posting about this issue, but my wife and I both have this problem.
The only real pattern I can find is that it seems to happen more when there would be a poor connection, such as when we go to our storage building (big indoor warehouse). But there are other times where my phone will be just sitting on the counter for an hour and I’ll come back to it and I’ll see that message.
Anyone else have this issue?
Edit: it’s been happening pretty much since we got our phones (day 1 delivery). So iOS 14-14.4, still occurring with 14.4. I believe I tried resetting my network settings at some point in time and it didn’t help. I suppose I could try it again.