The Terms of Services (TOS) for a Facebook Ad Account must be accepted before any audiences can be created successfully. The Terms of Services will only need to be accepted once for every Ad Account by the user who authorized the ad account within Advertising Audiences.
If you are having difficulties accepting the TOS make sure that you have the correct permission levels within Business Manager on the desired Ad Account. If you do not have the correct permissions you can send a unique URL to a user with the correct permissions for them the accept on their end.
Facebook Ad Account Permission Levels to Accept the TOS
To accept the TOS within Advertising Audiences:
000381600

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