ProAce Verso: transmission flushing

My ProAce now has about 90000km on the clock and I would like to have a transmission flush for the EAT 6 automatic transmission. The transmission shows no faults, but since it should last longer than the manufacturer defines the “lifetime” (160000 km), it is slowly time. I have now addressed two plants, which call themselves big as specialists. The first did not report back despite the second call, the second pressiest `rum, that you have to look, o b that goes at all (after he answered my question on the phone when I asked if this would still be possible “Why not?”. Say an appointment to watch, once an appointment for the obvious execution of the works. I am fortunate to have nothing else to do… Maybe someone here has insight and or experiences in the direction: Is this possible? Is this a huge number? What is the problem? Would definitely be grateful for every arrangement!