NWA50BE - Slow upload on 5ghz ch100 with 1% channel utilization

hello everyone, I've been having a couple of issues with this AP in standalone mode.

Basically I've 2.5g/1g FTTH connected to my router, which is connected to a 2.5g PoE switch, which then goes to this AP.

If I connect my laptop to the ethernet cable going to the AP I can see the full bandwidth so this makes me think the issue is not the rest of the infrastructure.

I tried changing all the parameters I could think of, including changing to ch36 (which is more crowded here, while I'm the only one on ch100), changing the channel width to 80 or 40, the transmit power and so on. no changes. Every test I do I get 1300mbps download (which is my laptop card limit), 200mbps upload. It starts around 600 then decreases and stabilizes everytime around 200mbps. Not sure if connected but 5ghz takes like 10 minutes to be available after a reboot.

Also I can't seem to be able to set 2.4ghz to BE mode or 40mhz width, the options are simply not there to change, but this is minor.

Any idea why this AP is hating me so much?

thank you