Zoom freezes after 20 mn

Starting yesterday. Every time I attend a zoom meeting, after 20 mn zoom freezes. It starts with the video freezing, but the audio works. Then about 5 minues later the whole thing freezes. I have to log out and log back into the meeting. Then is does the same after about 15 mn. It did it at three meetings yesterday.  All other browsers are working fine while this is happening. So it is zoom.