Maintenance for the week of October 5:
• [COMPLETE] ESO Store and Account System for maintenance – October 8, 8:00AM EDT (12:00 UTC) – 12:00PM EDT (16:00 UTC)
Make sure you have the materials as well. I've accidentally forgotten to make sure I have enough more then once.
If you need to, uncheck the 'materials' and 'knowledge' at the top. It'll show you all the options available. If you have the knowledge and the materials and it's still not showing up, logging in and out usually fixes that for me.