Welcome to RR.com!
The Pro-164 is a good scanner. However it is an analog voice only scanner.
"P25" is a nickname given to radio systems that use the
Project 25 specifications
for system setup & configuration. One of the specifications for a system to be classified as "P25" compliant is that the system uses digital voice for the system talkgroups.
Unfortunately the Pro-164 can't decode the digital voice used on a P25 compliant system.
You would need a digital voice capable trunking scanner like one of the ones in this
list:
Categoryigital Scanners - The RadioReference Wiki
Hope this helps!
Marshall KE4ZNR