Ibibo Group / Goibibo — Tickets not reserved for the reason of "one male and one female " passengers can't travel together

Address:

Aligarh, Uttar Pradesh, 202130

I booked two tickets for one male and one female passenger with seats side by side on gobigo from aligarh to noida upsrtc bus on today, 21 may for monday 23 may 8 am.
Ticket did not got reserved and a mail came saying "in progress"
After 4-5 hours i mailed regarding status but no reply till 2-3 hours.
Then i called customer care, customer care didn't responded in first call.
When got connected he gave me a totally rubbish reason of not reserving seats that "one male and one female passengers can't get reservation together". Can it be a valid reason, never heared of.
And if it is a reason then why at the time of reservation, no warning was given? Why it was showing "in progress" for hours? Didn't you put in your checks at website?