Does Zoiper ring at the same time if the softphone is busy?

Question

Telephony

When an agent is busy, already has an active call on their Zoiper softphone, and receives a second call while on a call, the audio from the call is played along with the voice of the person the agent is talking to.
How to solve such a horror?
Or is it solved through the guys who provide these services? We use Telfin.