After I replaced my rear strut last winter, I had to go to the dealer to reprogram the ZFE. (My new strut has a HALL sensor, the original one did not.)
I have to agree with schuppi.
Your previous ESA did not have a HALL sensor and therefore does not show in ZFE config (only HALL sensor type is in ZFE config). When they replaced the strut they did not update ZFE coding for the new strut.
But glad to hear that the calibration works.