The fibre-optic patch cable has a blue and a green end. The two connectors are different from each other even if they look similar by the eye. Please take care that you do not touch the sensitive ends of the fibre-optic cable after removing the protection caps. Insert the fibre-optic patch cable until you hear a click. A badly plugged patch cable properly can lead to malfunction.
Please patch the connectors as follows:
AVM FRITZ!Box 5530
SC/PC (blue) -> into the SC slot of your FRITZ!Box
LC/APC (green) -> into the fibre-optic socket (OTO)
TP-Link MC220L Media-Konverter
LC/PC (blue) -> into the optics of your media converter
LC/APC (green) -> into the fibre-optic socket (OTO)
Removing the fibre-optic patch cable
Press the small lever slightly together and pull the fibre-optic cable carefully out of the slot. Put the protection caps immediately on the end of the cable.