Unable to log RBP through SSH

When I first installed Umbrel on my RBP it got stuck synchronizing at 0%. That was due to the RBP not having set the right date and time. I logged through SSH from another network computer using the command “SSH pi@” and “raspberry” as password and set the right date and time.
Now I’m having the same issue because the was a few hours power cut and again Umbrel is stuck synchronizing at the % it was before the power cut.
But my problem now is different, basically I’m unable to access through SSH to the RBP anymore. It just won’t recognize the password (which I never changed). Any ideas on how to restore the RBP DOS password? Or Is there any other way to set the correct date and time?

username is not pi but umbrel . ??? what is RBP please use full sentence Raspberry PI ?

yes, that was it. Thanks!