internet way slow hardwired raxe300

What Firmware version is currently loaded?
What is the Mfr and model# of the Internet Service Providers modem/ONT the NG router is connected too?
Be sure your using a good quality LAN cable between the modem and router. CAT6 is recommended. 

Has a power off for 1 minute then back ON with the ISP modem and router been performed since last update?
Be sure to restart your network in this sequence:
Turn off and unplug modem.
Turn off router and computers.
Plug in and turn on modem. Wait 2 minutes for it to connect.
Turn on the router and wait 2 minutes for it to connect.
Turn on computers and rest of network.

What mobile platform are you using for the NH app? 

You sure the device IS connected wirelessly to the RAXE router? 

1. what modem/gateway is the router connected to? 

2. what firmware is on the router? 

3. have you tried a different ethernet cable between router/computer?

4. have you logged into the router and checked its wan/lan connection page to see what speeds its connecting at?

https://kb.netgear.com/24222/How-do-I-display-Internet-port-statistics-on-my-Nighthawk-router