Calculations and conditions sometimes not processing on form

Hello,

i have a few customers who are having trouble picking items on my store via my form. They are saying that the counter (max of 4 items to pick) is staying at 0 and so when they have selected 4 items the button to submit the form does not appear (as it has been programmed to in the logic conditions). 

Its not happening for all of them, but is happening for a few. Can you please take a look?

thanks 

Shan 

Thank you for contacting us.

The calculation and conditions are based on a browser JavaScript technology, so if there is some issue in a customer's browser it might affect the form. So far, your form seems to be fine when I check it on the desktop and mobile.

You may suggest customer re-load the form to see if that makes any difference. Also, if the issue is happening on some specific device and browser, let us know.