Network deteriorating very fast

I have been with Rain for a few years now. I was very impressed with the service and recommended my friends get the 4G package. I upgraded to 5G during their black Friday special in 2019 and although the upload speeds are usually below 1mbps for me and I literally cannot upload files larger than 3/4 mb in size I always made do with Rain because I mainly needed the download speeds to be good. However, in January towards Christmas and New years, my network quality began to deteriorate. I teach online from home but could not connect to zoom calls at all even when I switched off my camera and my student/s did the same too. I figured this was because many people were probably at home and I know the Rain network is very vulnerable to congestion. However, the problem has only gotten worse over the past few weeks. Both lights on the Router are on but "no internet available". The connection will randomly disappear for more than an hour and at this point, I always have to have mobile data as a backup which is costly. If the connection is not disappearing completely then it moves at a snail's pace more times than not. I literally have to cross my fingers that my lessons have minimal disruptions because the network has deteriorated that badly. Wishing for no disruptions at all is far-fetched. For the average user, this is already frustrating but when it interferes with your primary source of income even more so. Unfortunately, I have begun talks with Fibre providers and I think I'll likely be canceling this service at the end of the month. Never thought I would be rating one star but alas here I am.