On the call
If the person says things like "stop calling me", "do not call", or the Hindi and Marathi equivalents, the agent apologises, confirms it will not call again and ends the call.
After the call
The number is added to a shared do-not-call list. That list is respected by every Konvrs customer, not just you, and it stays in place until the person asks to be removed. Konvrs keeps only a one-way hash and a masked copy of the number, not the number itself.
Other ways to opt out
Anyone can also visit Stop calls to my number, prove the number is theirs with a one-time code, and be added to the same list.
Your part
Do not try to contact the person another way through Konvrs. If a customer asks you directly to stop, tell your team and keep your own records.