Hey there, AC.
Bo here from Shopify Support!
I absolutely love your page, it looks awesome. Taking a look at the product page on your site it would appear that the product-template.liquid is highly customized and this could be the issue at hand. Did you make these code changes yourself or did you have a developer make these changes for you? Were there any apps installed recently?
When did you notice that the variant drop downs stopped working? What I would recommend doing is go to Online Store > Actions > Edit Code. From the code customizer, you will want to open up the product-template.liquid. You will then want to roll back the file as per this guide. Each time you roll the theme back, click save and test out the drop-down functionality. You will then be able to determine which code change caused this issue.
Alternatively, I would recommend that you reach out to the developer who made the changes to the product-template.liquid to help resolve it.
Let me know how this goes and if there is anything else I can assist you with, I'm happy to help!
All the Best,
Thanks for your prompt response, Alex!
I was just speaking to our theme team regarding this, from what they can see, it may be an app that is causing this. In order for them to get a closer look, I will need for you to e-mail me at firstname.lastname@example.org from the e-mail you use to log in and get back to me in this thread with the reference number used so that I can authenticate you as the owner. Our theme team can then take a look at your account from our side.
I look forward to hearing from you,