SSH issues

The person who introduced us to gitlab has left the company. We have project that gets deployed to 4 servers. We can git pull the project on 2 of the servers. But on the other 2 we get this error: Permission denied (publickey,keyboard-interactive).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

My research tells me to look for keys in a .ssh folder on the servers in question, but none of them have one. Although 2 of the 4 work fine when we git pull

Also, when we enter git pull, it does not ask for a user name and pw - we get the error immediately

We are not using a self managed server