@Avskedsfest 

Did anything work there before?

Could be INTERFERENCE, there are pipes and other electronic 'things' in a kitchen. Still, it should work.

I'll assume the phone works well elsewhere?

Could try changing the Channel, or even the band if possible, there could be other SSID's closer by in this location interfering as well.

Try FORGETTING the network and then try to reconnect...

Try setting the router to NO SECURITY as a TEST and see if it can connect?

I'd try using the 5Ghz SSID if possible (I'll assume you are NOT using Smart Connect, if so, turn it off as a test).

@Avskedsfest 

With the antennas, they are omnidirectional but will broadcast in an oval pattern. So if you have a single floor residence then leave them pointing up like the box picture. if something was above or below you could try flattening the antenna to see if it is better reception.

What @IrvSp mentioned, what seems close to you is different from the wireless signals. 

@Avskedsfest The AC10 (AX1500) doesn't have that strong of a WiFi output...  Test with this cool tool: WiFi Analyzer by Kevin Yuan for your Android phone. It shows WiFi signal strength as you move around your house. You can try moving antennas and the router while checking the areas you have poor coverage,

By the way, antennas angled at 45 degrees give the best general coverage, due to the way the signal is polarized.

@Avskedsfest   Along with the other responses you may reset the router - unplug for a couple minutes then plug in the router and I highly recommend RESET NETWORK SETTINGS on all your devices.  I do this on my cell, tablets, laptops, etc about once a month or can simply put on the airplane mode for a couple minutes.  I had quite a bit of trouble with connection issues as well and rolled back the software but with the most recent software I believe from Dec 2020 has helped.  Not sure if it's possible (based on your device(s) wifi capabilities) but I honestly turn off the 2.4 ghz and have had much better luck.  I can speed test on my cell network, AT&T, here in Kansas City faster than the 2.4ghz can push out so why create congestion when there's no use for it.  Otherwise, I highly suggest the Wifi Analyzer and adjust your wifi channel(s) and if you keep the 2.4 on, I would change it to only to put out 20ghz.  

Good luck!