After trying to buy a couple of games from different vendors, I found that today things don't seem to work. After I click steam purchase I would usually get an invite from a bot, and a code to give it. However, today I get a message at the bottom saying 'Checking Steamrep status' and then nothing happens.

In before 'Your steamrep must be bad' : I have never been trade banned, and my steamrep comes back completely clean, I just checked. ;)

I assume this is a website failure, can this be fixed?

Would be better to know which bot it is and whether you could add it as friend manually. Usually it's a problem of not being able to add the bot as friend, for various reasons.