5G Home Internet signal on gateway says it is weak

We've had T mobile 5G home internet for a year, and it's saved us a lot of money. Unfortunately, though, sometimes it gets poorer.

After adjusting the gateway, I used to be able to get it to be "good," but unfortunately now it says "weak" no matter what I do.

My zip code is 07456, the gateway model is TMO-G4AR, and the model # is JT5091038, firmware release 1.00.12.

The gateway is pointed out a window toward the cell tower at the highest available floor, 4.5 feet off the ground. The app says not to point it at the sun, but currently that's where the sun is this time of day.