So i have a problem, I have a modem with 4X1Gbit ports and one 2.5Gbit port. My net speed is 2 Gbit/s. I have this TL-SG3428XMP and i wanted to connect the router from the 2.5Gbit port to one of the sfp+ port with an rj45 module. i have this module UACC-CM-RJ45-MG, it doesn't want to work in this scenario BUT if i plug the cable in a normal 1 Gbit port in the router and the other end is in the same sfp+ port and a change the sfp+ port speed to 1Gbit it works properly. I tried to change the sfp+ port speed to 2.5Gbit speed but i cannot because it said you cannot change the fiber port speed. I can change it just for 1Gbit or 10Gbit. Can somebody help me with this issue?