Good morning everyone!
First of all, I would like to apologize to you. This was not an issue with RRF but with my own code... Thank you all for your help and support!
Just in case, @gloomyandy and @AndyE3D you were right about M118 in every file in MMU Control. But I has no chance seeing something unusual until I used logging.
@dc42 I am sorry for tagging you here and wasting your time.. was my fault, not RRF's fault..
The problem was elsewhere, right at the beginning, in tpostn.g.
There, were three simple calls: load the filament in the MMU, then in the extruder and last in the nozzle. If during those macros any error raised, the tool change macro continued showing a dialog (M291). But, it can also call errorAction.g which by itself loads the filament all the way to the nozzle, but being called from a "while" loop in tpostn.g, after errorAction.g the while loop was trying to load it again to the MMU. The log confirmed that:
2023-08-02 12:02:28 [debug] Finish: loadToBondtech.g
2023-08-02 12:02:28 [debug] Begin: idlerMove.g
2023-08-02 12:02:28 [debug] Finish: idlerMove.g
2023-08-02 12:02:28 [debug] Begin: loadToNozzle.g
2023-08-02 12:02:28 [debug] Finish: loadToNozzle.g < here the duex.e2stop is configured as a filament sensor
2023-08-02 12:02:28 [debug] Begin: loadToFinda.g < here the duex.e2stop is used to load the filament in the MMU
2023-08-02 12:02:35 [warn] Error: Pin 'duex.e2stop' is not free
2023-08-02 12:02:35 [warn] Error: G1: Failed to enable endstops
2023-08-02 12:02:41 [info] Event logging stopped
In tpostn.g adding a break statement to exit the wile loop solved this problem
Thank you again to all of you for your support! 