Eufy Security 2K - RTSP failing continuously

I have two cameras and I use them as baby monitors. I have both configured as RTSP transmission (continuous recording) to see a live streaming. I use VLC as client.
I have a good house network, a mikrotik router and two ubiquiti access points.

Lately they work really bad (at beginning they worked better). The transmissions are continuously stopped, even I have to restart the cameras or switch off/on RTSP option, but even doing that they still fail.
Notice that with Eufy iPhone app the streaming works fine.

Does someone know what is happening? Why Eufy app works better than local RTSP? Theoretically RTSP should works better since it is a local transmission.

Thank you!