Only a few lines show up in the window. I don't see any numbers anymore.

Bad sensor or bad screen. Is there s battery in this model controller?

No battery is included.

Then you have a problem with either the pressure sensor, or the readout and should contact the mfgr

You have bad soldier joints. This happens on electronics sometimes. I have cured the problem by baking the part in an oven at 450 degrees for 8-9 minutes as with a formatter board on an HP printer, but you cannot always do this as some things will melt at that temp. Is it under warranty? It may be a common problem that has had a recall notice.