Maybe its some memory issues, I would try to test the sketch without the display, and remove all display code inclusive removing the declarations #include <Adafruit_GFX.h> #include <Adafruit_SSD1306.h>
You have already successfully tested that code with display is working fine, now you need to test the Mysensors code without display code.
If this is successfully, I would combine the codes, but remove debug, remove all code for Serial.print, and remove #define MY_DEBUG
