We Were Not Allowed To Board Our Turkish Airlines Flight Despite 20 Minutes Remaining

On 15.03.24, three of us checked in for flight TK2838 and sat near the gates. Due to my son's allergy (which can be seen on cameras as he was struggling to breathe), we didn't immediately join the boarding line. There were more than 20 minutes left before the flight's departure, but we were not allowed to board because the gate was closed. The attendant said the gates were closed, boarding was finished, and directed us to the counter for a new ticket. She mentioned an announcement was made, but then said the airport was quiet so no further announcements were made. This isn't my first flight; it's clear that three people checked in two hours prior and were nearby. I've seen attendants ask around in similar situations before. I believe this was either an overbooking issue or a personal problem. It was iftar time, possibly a shift change, maybe the attendant was tired or didn't want to deal with us, or it could be due to an attitude towards foreigners. She didn't even look at us, provide an explanation, or offer any assistance. We were only visiting a sick, elderly grandmother for two days and were forced to buy new tickets. The airport is very large, and by the time we reached the counter and waited in line, we couldn't get a discounted ticket, nor could we get a refund for the return ticket. We had to spend ₺6,700 for new tickets. During the 5-hour wait, we had to eat, incurring extra expenses. For the next flight, I stood at the gate an hour in advance and we were only allowed to board half an hour later. On other occasions, people are still boarding with 20 minutes left and no one closes the gate in front of them. If this happened to Turkish men, there would be a big argument. I request that this issue be investigated and our grievance addressed. Thank you.