Asus RT-AC68U weak signal

Hi folks

I have Asus RT-AC68U and I am having some issues with the wireless range.

I am connected to the router with Asus PCE-AC68 adapter and only getting 70Mbps from a distance of 30ft on the 2.4GHz band and my iphone is not getting signal at all.
I feel that this is not normal and I should be getting a stronger signal.

After doing some research I am considering replacing the device with Netgear nighthawk X4S (R7800) but I am still not sure if that would improve the wireless range.

I...

Asus RT-AC68U weak signal