Just to be sure — you uploaded the public key to your servers, right? In your user's directory on the remote server at ~/.ssh/authorized_keys. Your private key should never leave your system. That's a very common mistake in my experience. The wording of your post makes it seem like you may have done that.

Let me make sure I understand first

1. You are attempting to passwordlessly SSH from Window to a group of servers using Powershell
2. Something stopped working and you regenerated your Windows SSH keys

i added my private key, and tried to connect

This concerns me, as the server should have the user's public key, not private. Private should be exactly that, private

Is the Powershell user / SSH key the same as the Putty user / SSH key that still works?

When you run the Powershell script, does it give any error messages?

I know with Linux -> Linux SSH you can log verbosely with -v, is that something you can do under Powershell?

Is password auth enabled? Does that still work from Putty, and can you do the same from Powershell?

i added my private key

You are supposed to copy your public to the server, not the private one.