Issue with product quantity being multiplied by several thousand during checkout

[Ploutone]

Hi all. Several of my customers have reached out to let me know that their order quantity has been multiplied on the checkout page to the point where their order totals are in the millions, and they are not able to able to resolve the issue themselves. The last customer told me that it appeared as though the quantity was multiplied by the digits in their zip code. When I send them a draft order with their shipping address, there is no issue, but it is apparent now that it is happening frequently enough where it is a serious issue. I reached out to Shopify support, and they were unable to help since neither myself nor them have been able to replicate the issue on our end. They suggested to reach out to the provider of my stores theme, which is Wokiee from ThemeForest, but they don't have the fastest response time and I am hoping to find some assistance here. I would be so grateful for any help here. Cheers! Store is: www.ploutone.com

[Ploutone]

Hi Stefan. Thanks so much for taking the time to check it out. Myself and Shopify support had the same experience and we were unable to replicate the issue with the products and zip codes entered by my customers. However I've had three customers in the past month reach out mentioning the issue. I am at a loss at the moment. Thank you again for trying to assist me.

[Ploutone]

So I've been messing around the cart page all night and I figured out that the order total is being multiplied by the zip code only when someone hits the "calculate shipping" button after entering their zip code, but I still have no idea how to fix this