mohamed abdallah wrote:

Please be aware that Egypt has ceased using the daylight saving time since 2016 and although this fact our android smartphones keeps changing the time (GMT+2) to the daylight saving time (GMT+3).

The Time Zone Database addressed this issue in release 2016f dated 2016-07-05 16:26:51 +0200. My Android 8.1.0 phone (security patch level 2018-09-05) currently shows Cairo (+0200) as being nine hours ahead of Los Angeles (-0700), so it appears to be correct. Possibly your problematic phones are running out-of-date software, which needs to be updated. I suggest contacting the manufacturer of your phones and/or your wireless carriers.