Strange lumbar support malfuction

[NOSDylan]

Got a strange problem with my electrically lumbar support. I'm not from a English speaking country so I'll try to describe the problem as clear as I can.

 

The lumbar support has 4 adjustable directions. Up and down of mine work well. The problem comes with the in and out direction. Normally, if the lumbar support is in the outermost position, by pressing the left button it'll go back in and stop at the innermost position, and the adjust motor will stop working.

What happened to mine is that if I continue to press the 'in' button when the lumbar support is already at the innermost position, the adjust motor won't stop, and the lumbar support begins to stretch out, eventually stops at the outermost position. At this situation, if I press the 'out' button, the lumbar support will go back in till its innermost position, then come out again until it reach the outermost position.

 

Did a research on the lumbar support structure but didn't find anything useful. The lumbar support is powered by a motor and some metal wires rather than an air pump. Had the switch changed but didn't help.

 

Any idea where it goes wrong? Thanks!