Dobot magician 4.0.3 firmware help


I’am a teacher,in our class we have 10 dobot magician, 2 of them have the same problem, status led off and robots don’t move.
I saw that firmware in Dobot Studio have a older version 3.7.0 than the robot 4.0.3 .the “broken” robots have 3.7.0 but the other have 4.0.3
I think that some students have flashed the 3.7.0 using the dobot studio command making mistake.
Could you please say me where I could find 4.0.3 firmware? In dobot site there is only 3.7.0
Mauro Galvan