I can't add the feat Ritual Caster to my Warlock, doesn't show up under manage feats

Hello,

I'm trying to add the feat Ritual Caster to my warlock character, but when I go to manage feats, ritual caster doesn't show up. I believe I meet the prerequisites for it as I have a wisdom score of 15. I would show a screenshot, but I can't seem to paste it onto here.

Any help would be appreciated.

I think I have the Player's Handbook, but it''s just not showing up at all, and I can't buy the feat individually either. I'm at a loss. I guess I'll just manually add the feat somewhere.

Thank you for your response.

Correct, when I went to Manage Feats, Ritual Caster didn't show up anywhere. Not under Core Rules or 2014 Core Rules or Unavailable Feats.

The good news is that I just asked my DM to add it, and he was able to. :)

Thank you much for your responses. Now I know for the future where to check if I may or may not have the sourcebook material.

I also just checked and it turns out I don't have the Player's Handbook, so that explains that. Ooops.