That doesn’t look like key issues, it looks like wrong IP - like another device with no ssh sever.
Run ssh with -v and see what is really going on before guessing on remedies.
Once in a blue moon i need to reboot my phone or router for odd breakages like this. But i assume you have done basics like that before asking?
And also, didn’t you have the same issue before?
Yes, yes you did: SSH + SFTP access to phone lost