Why doesn't video playback work on IOS?

Question

iOS

Hello, gentlemen, I ask for help, there is a project - we are making an application for viewing video cameras online, based on open source software on Linux, which writes video from cameras in mp4 format to a separate folder on a PC, and so, we made the so-called " Timeline", for easy search of the right moments. when you select the desired video on the timeline, it should start from a certain moment, for this there is an exact time on the timeline up to seconds, AND HERE IS FINALLY THE PROBLEM ITSELF, everything works as it should on android and PC, everything loads, shows, everyone is happy, but on iPhones The page freezes and reloads, we can not understand what the problem is.
Please see if anyone knows the solution, of course not for free!
https://signum56.ru/login
[email protected] - Login
testkwork - pass