Please try the following:
Go into “Product tabs -> All Product Tab Types” menu in wp-admin area, edit one of your tab type, and ensure that “Use for all products” checkbox is on or the appropriate product categories are selected on the right.
Then please go into “Product -> Products” menu in wp-admin, you should find wysiwyg fields with “… tab content” label. You should enter your tab content here.
The warning you attached means that there is no tab page type entered.
If you check all of these settings and the problem is still exists, please attach screenshots about Edit page of one of your product tab (Product tabs -> All Product Tab Types -> Edit), and edit page of one of your product (Product -> Products -> Edit), about the screen area under the “Product data” section (so not the product data section, but the section that follow it.)