magento2 – can’t update a page template

Hi all and nice to meet you.

Some days ago I’ve modified vendor/magento/module-catalog/view/frontend/templates/product/view/addtocart.phtml in order to add a static phrase to every product page.
I know it’s not the right way and i should rather override in app/design/ but it worked and it was only for few days.
I regenerated di, static and cache:

php bin/magento setup:di:compile
php bin/magento setup:static-content:deploy
php bin/magento cache:clean
php bin/magento cache:flush

Everything worked and the phrase was online.

Now I’ve removed the phrase from vendor/magento/module-catalog/view/frontend/templates/product/view/addtocart.phtml. I do the regeneration of everything (di, static and cache) and the phrase is still there. I search for the phrase in the filesystem and it’s only inside var/page_cache files.
Why regenerating the cache put the phrase in if it’s not present in my templates?
What I’m doing wrong?