Replacement for 3G MicroCell

For years I had a 3G MicroCell that hooked into my internet; I got it because my calls drop here at my apartment without it. The signal is so bad here I get only one bar, even outside my apartment, and nearly every call drops or at best, the call is peppered with many 3-second drops in audio or sometimes, horrible static.

I can't use it any more because it won't work with my iPhone 7 and even so, it's being discontinued in February.

Does AT&T have anything else?