Variable Product Text Attributes not working?

I am building a site with many products that will all have exactly the same text attributes.

All the attributes are of the type “text”.
I have added these attributes to the global Products->Attributes page.

When I select a product it’s “Product Data” is set as “Simple Product”.
I understand that if I want to make my global attributes available I need to set “Product Data” to “Variable Product”.

Once I change “Product Data” to “Variable Product” the price field under the general tab vanishes.
I then click on the “Attributes” tab and add my global attributes as defined earlier. I ensure that they are “visible on the product page” and that they are “Used for variations”.
I make sure I “Save Attributes”.

Now, when I click on the “Variations” tab I get a the message “Before you can add a variation you need to add some variation attributes on the Attributes tab.” and a button that takes me to documentation.

If I update the product and refresh the page my Attributes for the product have vanished.

Please advise.

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