my temperature gauge seems to have stopped working?

Now, today, my temperature gauge seems to have stopped working (just sits at low and doesn’t move) and both radiator fans stay running all the time while vehicle is running. Display instrument information panel shows engine hot a/c off and service tire monitor system, check engine light is on and (blinking) yellow exclamation point is on.

Heat works and vehicle doesn’t seem to be overheating really, even though the above is occurring.