Had and used one of these they are horrendous.
We can offer you a bunch of decent ones. Namely get a Netgear AC wireless repeater, they stay connected months on end. I had one with over 6 months uptime.
Placement is key, it needs to be in a good signal area which also reaches the not-spot area. It usually makes sense to place them halfway between the no signal area and original router.
I think I had this, was over a year ago now so might have been a different model:
I manually set mine up to be one unified SSID - out the box it adds _EXT5g on the end of the SSID
Edited by ukhardy07 (Sun 10-Dec-17 02:34:10)