Radcity shifter broken

[Winterhawk]

We have 2 Radcity bikes so easy to compare one to another. One quit shifting and stays in 7th gear. Thought it was cable or needed adjustment but all that stills works as it should if cable is loosened. Problem is in shifter because it doesn't hold a position when down shifting. The other bike works perfectly and you can hear clear clicks up and down shifting with cable loose. Not so with the other shifter. The lever moves but doesn't click into each gear. Anyone have a solution, or do I have a broken part inside shifter preventing it from holding a gear. There must be a pawl or something inside to keep it in each gear.

[DCH3416]

Sounds like it may be a broken shifter. You can get a replacement part here: https://boltonebikes.com/collections/frames-and-parts/products/shimano-7-speed-thumb-shifter

[Winterhawk]

Not worth the hassel of trying to figure out. Ordered new one because I'm possitive its broken.

Thanks!