API key for stripe has changed without my knowledge

Adan

My payments weren't working and due to a lack of any support from Wave I reached out to stripe who have been amazing.
I sent them a link to my invoice checkout page and they noted that the Stripe API key wasn't to my stripe account!
I have received payments in the past and I have never changed the key (I wouldn't even know how to!). So what is going on here and what can I do to fix it please?

Really hoping someone from the community can help as wave support is non existent and now I have missed out on being paid today.