That doesn’t look right to me I think it should be:
$(".inputboxmodal1").on("blur”, “.input-check",function(){
console.log('changed');
Note the closing quote and comma after the word blur.
Also now that input-check is the source of the tracked event then $(this) will refer to the input-check element and you therefore won’t need to find it as you are trying here.
var inputattr = $(this).find(".input-check")
$(this) already refers to input-check.
I’m not back at my computer until tomorrow but I think you need more expert js help than mine 