Users cant use Steam login feature on my website

Ive been trying to figure out why nobody can login with steam. It just gives a 500 Server error and nothing else.
Also, when i tryed logging in with steam on prometheus (a donation system for games and servers) it said no OpenID server found.
How do I fix this? And i need it fixed asap

Update: I get an error now:

Fatal error: Uncaught ErrorException: No OpenID Server found at in /home/vol2_5/ Stack trace: #0 /home/vol2_5/ LightOpenID->discover(‘http://steamcom…’) #1 /home/vol2_5/ LightOpenID->authUrl() #2 /home/vol2_5/ steam_redirect() #3 /home/vol2_5/ steam_output_to_misc(‘’) #4 /home/vol2_5/ pluginSystem->run_hooks(Array) #5 {main} thrown in /home/vol2_5/ on line 515

Access to the Steam API has been blocked for security reasons. Unfortunately, there were too many people using it to do bad stuff (like hacking, spamming, phishing), which is why we were forced to block it entirely on free hosting.