These “repeaters” and “range extenders” are very often real truble causers.
Avoid using them.
If you have to, don’t mix manufacturer brands. Also don’t mix new and old WiFi devices (like using an older wifi router and a newer repeater or viceversa) as they may implement standards differently, causing malfunctions.
If there’s no other way to avoid this, use different SSIDs for the main and for the “repeated” signal, so that clients like OS don’t get confused.
But better, try using quality AccessPoints, like Ubiquiti UniFi.