How do I get my public key once the machine is made?

Hello, I have been using a oracle cloud server for a while but only today I've had a connection issue where its no longer accepting the public key which I've been using for the past year, I first found this issue on my phone I thought it was a issue with my phone then I tried it using putty which I have been using regularly to connect to the server also doesn't connect, I tried the live chat support but because I don't have a paid account I don't have access to it so I came here looking to see