Satellites don’t get re-positioned, they are in orbital planes and slots, to move them is expensive in time and fuel, thus, once they have been placed, they stay. You can see how the constellation operates at starlink.sx - you’ll quickly notice why coverage is a function of gateway availability, the constellation has enough density.
The issues in the US are twofold - many customers added while not enough satellite capacity is available (the first constellation is only about 50% complete), and many gateways only have half the spectrum available, reducing available througput.