Check your current build on the main menu. Updates like 1.6.0.119 or the 1.7.0.13 Experimental branch significantly rework the Enfusion Engine, making older trainers obsolete.
Arma Reforger Trainer Fix: Troubleshooting Guide & Solutions Arma Reforger Trainer Fix
Because trainers inject code into the active game process, they are frequently flagged as "false positives" by security software. From SQF to Enforce Script – Arma Reforger Check your current build on the main menu