I just had the same problem today…Except I have not updated my printer since March, or even used my printer for over a month, and I could not get BS or the Handy App to see the printer, which passed all network tests. So it might be a Bambu Handy App issue after update that nobody has noticed that is causing this, and are blaming the printer firmware or BS software.
Here is what I did - Started from scratch on the printer “Scan qr code with phone and Handy app” then ultimately rebind my printer with the app. Then all my issues went away - even BS could not see it until I did that.
I STILL HAVE NOT UPDATED MY PRINTER FIRMWARE OR BAMBU STUDIO!
Hopefully this helps some of you out.