They just recently added a voice fraud detection system where if a subaccount calls a contact more than 2 times in a 3 minute timeframe, the subaccount cannot call that contact until 15 minutes have passed. If a call is made within that 15 minute timeframe, it resets the 15 minute timer. I have confirmed this with support.

The problem is that currently the error message shows that the issue is happening because a user is currently on the line with the contact. The exact error is: "Cannot connect this call Active call from your account to the dialled number already exists". And yes, they misspelled "dialed". But anyway, the error message is incorrect as that is actually NOT what is happening and what is actually happening is what I mentioned above.

They need to reword the error message to state that the voice fraud detection kicked in and a 15 minute cooldown is in place, showing the remaining time if you hover your cursor over the exclamation mark next to the call in the conversation logs.

In addition, it should not count towards the Voice Fraud System if the contact was set to DND-Call. We had an issue where a client was calling multiple times, unaware they were DNDed. We removed the DND and we still couldn't call them. It doesn't make sense since the call never reached the contact.