Lower speeds on wifi extender?

I got a wifi extender, prolink at the start of this month. The speeds were much better on the extender, while I only got 2 bars from my router which is downstairs and constant coection drops and slow speeds. But now however my extenders speed is just slow, I get full bars however the speed is about 3-4 mpbs while when I am coected to the my router, the speeds go to above 7+ mpbs. I have no idea what is going on.

I would also like to point on when I set up the extender, it automically cotected to my router but I can not access the extenders IP to conifg it, which is "192.168.123.253". I cant access that site from my extender or my router.

Anyone know what is going on and how to fix it or a way for me to access the extenders IP so I can config it.