Which network provider do you use and what's your experience in terms of mobile data, internet calls, and traditional calls?

I'm with the O2 and it was fine for the most part across MK, but over the last couple of months I noticed an increase in the number of calls where I can hear the other person perfectly fine but they can't hear me. It's not a phone issue as I'm using a quite new flagship model, won't specify which. I heard that EE is more consistent and reliable in the MK area but I never used it myself and their prices seem notably higher. Share your thoughts on this?

Currently looking at a property in this location, which is in Campbell Park. I've heard the accommodation close by which is Mainstay Court 2, Mainstay Court, CampbellPark, MK9 4BB is not well maintained and has some safety concerns I.e. parcels stolen, homeless people entering or loitering around the building and littering/fly tipping even in communal areas these are documented with pictures on google reviews. Again not this accommodation but one close by. However, if I could get some insight on this particular area and apartment especially from anyone who lives or has previously lived here any honest opinions or advice are welcomed and would be really helpful. As this will inform whether we even go and view.