catextlayer doesn't show

Hi all,
I'm trying to make an animated button which includes 3 layers where one of them is composed of CATextLayer.
the CATextLayer is showing and animating fine on Iphone 11 OS 13.0 but doesn't show at all on iphone 7 OS 11.0.

what can be the cause to that?
catextlayer doesn't show
 
 
Q