The Cudy P2 5G router won't connect to 5G

Good morning, the router won’t connect to 5G even though I have a strong signal with external antennas; even on the 4G LTE band, the speed doesn’t exceed 53 Mbps, whereas with a smartphone and the same SIM card, the speed is 70–90 Mbps.
The modem firmware version is RG500UEBAAR03A08M4G_01.300.01.300. Can I get an update that will resolve the issue?
My email is giuibigaz@gmail.com
Thank you