Add to Cart Button "There was an Error and we were unable to add this item to the cart"

My client is experiencing an issue where their clients seem unable to add items to the cart. The button gives the error “There was an Error and we were unable to add this item to the cart” OR “The item is not available in this quantity”. For most people, this seems to work fine, but on some devices, clients are unable to add ANY items to their cart. I can’t figure out if it is a browser issue or a device issue - my client doesn’t know how to ask for that info.

Some things we have tested - The device that experiences it the most is an Iphone 11 Pro MAX.
All my devices seem to load it fine, so a samsung 21s, a PC on chrome, and emulating it as an iphone device. I haven’t gotten around to testing different browsers, but likely it would be an issue in Safari if the device is apple.

Please let me know if anyone has any insight into this issue! Thanks!


Here is my site Read-Only: LINK
Link to live site: www.lvlenka.com