Copy this from the switch
example:
1/2/1 ADTN1517099F
this shows:
Device/Card/PON ONTSerialNumber
##Card## = card, 2 digit with leading 0 if necessary, for example 01 or 02 or 03 or …
##PON## = port, 2 digit with leading 0 if necessary, for example 01 or 02 or 03
##ONT## = number of ont, 2 digit with leading 0 if necessary, for example 06, or 23