Can't set time zone (by 4 users)

Acurite 00592W model clock.
I just purchased two of them and the instructions do not work.
To set the time zone the instructions say to press the "-/C/F (Zone)" button once to select PST/MST/CST or EST time zones. They also state that a small P, M, C, E icon will appear to the left of the itme display. It just doesn't work. Pressing the button changes the temp displays from C to F degrees. Please help.

Can't set time zone.

cannot reset time zone at end of daylight time. need manual. I have pushed every #%&#@x on the watch and every combination.