Why do I keep receiving emails about API limit reached?

Ive tried to remove parts of the form that was using API from what I know about it.

Ive turned the forms off (disabled - what does that actually do?) and still i get emails saying ive reached limit. No one is even using the forms, why is this happening. Can someone advise me what to do?

I have checked your API info in your account and I can see there is not any in use, I have also found that you have received the last email about reached your API limit yesterday (July 6th, 2016).

When did you remove the APIs you were using?

If you're still receiving these emails even when you're not even using the API then this should be reported to our back-end team. 

Please let us know when you removed the APIs you were using, we will wait for your response.