How can I fix a Javascript issue that changes product prices on my website?

Hey folks! I hope everyone is well.

I’ve implemented some code on our site which inflates all product prices by 20% (we run wholesale & retail, so we keep the prices with VAT removed for this reason).

This works well in practice, however with products with multiple variants when the user selects a different variant within a product on the front end, the price reverts to the lower (minus 20%) price.

I’ve deduced this is a Javascript issue, however my knowledge in this field is zero.

I’ve noticed there are a few references to price in our “theme.js” file, however I’m not 100% which section I should be looking at and how to tell the JS NOT to adjust the price when a new variant is selected.

For reference of this in action, I recommend looking at this product - you’ll see the price is £3.98 (which is the +20% price) and when a different variant is selected, the price returns to £3.32, which is the price inputted into Shopify.

Shopify won’t allow me to post the full theme.js file in here, so here’s a link to a google docs file with the code inserted.

Any help would be much appreciated.