wifi connection unstable or dropping on video calls

I cannot take a video call (on any device or service—Zoom, Google, Teams, etc.) without it freezing and saying my connection is unstable—even though ten seconds earlier it was fine. This happens repeatedly throughout the calls, making it impossible for me to do my job. I have tried pausing every other device on my network while taking calls, and I still have the same issue. I am new to Xfinity and have never ever had this issue with any other provider. Please help.