I am a newbie and perhaps this issue is incorrect. I am going to connect raspberry (3B+) with the laptop, then connect it via OpenSSH (OS is Windows, + WSL) or VNC. I am using mobile internet.
About 2 weeks ago I could have an access to raspberry pi shell. But I had
apt-get update error. I read similar issue, where it was recommended to reboot the OS Raspbian and try again. I tried it several times, but it doesn't help. I used as balenaEtcher, and win32diskimager too.
Host name was 'raspberrypi.local', it worked. Now I tried also 'raspberrypi', 'raspberrypi.mshome.net' and several IP addresses.
A little change in my issue: I had access to raspberry session, but it's inactive. It shows:
WARNING POTENTIAL SECURITY BREACH The server's host key does not match the one putty has cached in the registry. This means that either the server administrator has changed the host key, or you have actually connected to another computer pretending to be the server. The new ssh key fingerprint is:................. ..............(I suppose, there has written ipv6 address)
If you were expecting this change and trust the new key, hit yes to update Putty`s cache and continue connecting. If you want to carry on connecting but without updating the cache, hit No.
If you want to abandon the connection completely, hit Cancel'