I'm trying to overwrite a file belonging to the Amasty Single Step Checkout from within my custom theme. The file I'm trying to overwrite is:

vendor/amasty/module-single-step-checkout/view/frontend/web/template/onepage/2columns.html

I'm trying to do so by creating a custom file in my theme:

design/frontend/MYVENDOR/MYTHEME/Amasty_Checkout/template/onepage/2columns.html

after clearing cache and deploying my theme it doesn't seem to work, wht am I missing?

I'm in developer mode