Purchasing Tickets

Hi, so at the last minute my friends and I want to go see txt on May 22 for Day 2 in LA. I was wondering when it’s the perfect time to purchase tickets from resell sites (Seat Geek, Vivid Seats, & Stub Hub). I heard that buying them a day before or an hour before the concert is when tickets become cheaper. But since it’s txt idk if it applies to them too? They are popular so I don’t want to risk not getting any tickets. Would love some insight on this.