If you have missed accepting the Terms of Service for your Ads Account, you can accept the terms here: https://www.facebook.com/customaudiences/app/tos/

When you receive an error while using our tools indicating as terms of service not accepted this is because you haven't accepted the terms of services on your Facebook ad account. To be able to continue using our tool and avoid this error in the future, please read the terms of services on the link provided and once you agree with the terms you click the Accept button located on the top lefthand corner to accept and agree with the terms of services stated.

How to get your support tickets resolved faster
Statistics have shown us that the more you tell us when you report an issue, the faster we solve that ticket. So...
1 - If you have screengrabs, please include them. A picture is worth a thousand words.
2 - If you have recorded a video showing the issue you're having, please include that as well. A video is worth a million words. We recommend a free service called Loom for creating these videos. (this is a link to useloom.com)
3 - To speed up ticket resolution, follow these useful tips How to Write the Perfect Support Ticket (That Gets Results Fast)