It happened all the time with my phone, too. I could only conclude that I was inadvertently adding a twist every time, without realizing it.
the good news is that, regardless of how it happens, you can get rid of it without the bother of undoiong your phone connection every time. (I myself liked to dangle the receiver without disconnecting it, just to watch it spin, but that’s just me.) —
Get yourself a rotatable phone connection. You can buy these at phone stores and office supply stores. It allows the wire to rotate freely, so kinks never develop. After i put one on my phone, I never had to worry about it.
What I really wanna know is how my daughter can manage to kink and knot her Slinky, in a way that suggests that she’s been rotating it through the fourth dimension. It takes a least half an hour to undo it.