Slow Home Internet

Having exactly same problem with slow home internet. If it doesn't get fixed soon may have to go back to cable which I really don't want to do as I left them for a reason. Tm home internet Started out at about 100 to 200 mbps. Now it's about 20-30mbps and videos buffer all the time. My phones still get good speeds, the 5g phone gets 300-400mbps on speed test but my 5g home internet is only 20-30mbps. If management is throttling home internet to only 20-30 mbps then I'll have to leave b/c cable is 200+mbps or greater consistently. Was expecting to get similar service on home internet as I do on my phone but it isn't happening. Spending a lot of money with t mobile and expect high speeds on ALL devices all the time. Especially the home internet, which should be highest priority on their network as we use it for work, meetings, school etc...