I have a SP2010 Foundations site and I was editing my content pages and using the HTML option to make small tweaks here or there. I've created my own Master Page and added my own CSS as well. Things were going great, then I added some more pages into the Site Pages library and now the new ones and the old ones don't have the option for HTML anymore, it's just Styles and Text Layout. The Markup ribbon toolbar option is gone. No option to edit HTML or select my HTML styles like H1, H2, etc.
How do I get it back? I don't get why/how I lost it!