AR750 Constantly Disconnects

Here is my issue I have an ar750 and it constantly disconnects from its connection and does not ever reconnect, ive only had this router for 2 days and ive had so many issues with it. Need help

-how im using this router it connects to the main wifi in the house 2.4g (have no access to 5g) in repeater mode it never stays connected always disconnects and never reconnects, this router has been unusable since i got it…

Firmware used - openwrt-ar750-3.027-1009.bin (this was recommended to me for connecting to Hidden ssid networks)

How far is the AR750 from the main wifi?
You can set the wifi rate down to 144M or 54M to improve stability

How do i let it auto connect once it disconnects. this router does not auto connect even when the option is enabled…

its doesnt let me edit both speeds tells me that i cant edit if in repeater mode.

You need to disconnect the repeater first and then change the speed