Hello! I use an Archer A9 wireless router. I have an internet subscription with a speed of 1000 mb / s via fiber optics. I use a Tp-Link Archer T3U AC1300 adapter on my computer. I am also connected to the Archer A9 with an Apple Iphone 11 device that is capable enough to set high speeds on the wireless connection. Neither the wireless adapter nor the mobile phone can reach speeds higher than 308 mb / s on the 5Ghz band. The internet provider has an OTN device installed in my apartment that acts only as a "bridge" for the Archer A9 router. So, the connection that enters the Archer A9 is gigabyte but even so, on the 5Ghz wireless network my devices do not count at speeds higher than 308 mb / s. What could be the problem? The cable between the OTN device and the Archer A9 is of good quality. Thenk You!