Dear Mr. Dasgupta,
I think with your mobile remaining busy, they can just SMS you to confirm the details or ask for a suitable time to call, after all the SMS will be recd in the same mobile and its a much cheaper alternative (though involve little charge for the customer to send reply) !!
Hope your seller would definitely understand your situation.
Regards
Swarup Dutta
.
Best Regards
๐
Swarup
Kolkata
