sunrise network in the leimental and the birstal

I don't know why but it seems like sunrise isn't taking this area seriously, for example there are only about 3 cell towers in reinach (a spread out town of 20000+) all close to the highway compared to salt and swisscom who have towers evenly spread out. and a similar thing in other smaller villages like therwil and ettingen, where the only tower is at the very center so there is bad signal in the edges. This is fine outside but dare I go throu a wall there is no signal.