Despite most of the signal metrics being serviceable, signal to noise and interference ratio value is poor, around the disconnection limit. This would indicate that you are located in there are some noises of interference. It could be other signals operating in nearby frequencies, for example, interference from the same or adjacent frequency bands due to multiple users communicating in the same frequency band, or multiple cells using the same frequency band in the same area, some external electrical equipment or atmospheric disturbances. This might also be related to changes in your provider's network as well.
What you could do is to try using a different LTE band. For instructions, on how to lock a specific LTE band, refer here. The bands to try are: B1 and B3.
See if that gives any improvement.