MailChimp API not working with Membership2 anymore

When I was looking through some backend stuff, I noticed that Mailchimp seems to be broken, and the API not working. I clicked the link to get a new API, logged into Mailchimp, and proceeded to get 2 new APIs, none of the 3 worked.
I clicked on logs and see:
[March 7, 2017 12:56 am] [CODE:503] - Unknown error, call getLastResponse() to find out what happened.
[March 7, 2017 12:56 am] [CODE:503] - Unknown error, call getLastResponse() to find out what happened.

but I have no idea what any of that means or how to fix it...
I looked and saw someone else had the problem, but his solution seemed to involve a lot of code that I had no idea what it was. Either that or it was written in a foreign language...

thank you