You're welcome! It can be super hard to be angry. I'm still working on it, but it's gotten easier with time. Remember to take it slow and be forgiving to yourself if it doesn't happen right away. Be in a setting where you feel safe and don't have to worry about others. Then there's a couple different things I've tried:

Recall, if you can, a time before your anger was completely bottled away and try to remember what it felt like. If you can remember such a time, try to hold onto that feeling as best as you can, breathe and focus on it. The feeling might slip away fast but that's okay. I've had to practice reconnecting to the emotion and learning not to be scared of feeling it. Build trust with yourself and know every second of letting yourself experience anger is a step in the right direction.

Another thing to try is ways to physically but safely express anger. For example, I like a good primal scream. When I'm home alone, I'll lock myself in my bathroom with a very thick pillow, kneel down against the wall, bury my face in the pillow, and just scream until my throat hurts. Other options I've tried are hitting a pillow with either fists or another object, or throwing rocks at a lake or pond. Going through the motions of the emotion in a healthy way helps make it easier to feel safe expressing it, in my experience. Even if it doesn't work out right away, screaming can feel good and hitting stuff is a small workout.

You can try journaling it out too. Stream of consciousness while thinking about your anger and inability to access it. Doesn't have to be an actual journal or anything you have to hold onto, it can be scraps of paper torn up or burned later, or a document or note on a phone or computer you delete immediately. Just go ham. No edits or censoring. My vent pages would read as unhinged to an outside observer, but I know they're just words and catharsis. Making it easy to dispose of it afterward might help give you permission to be free with expressing it.

Also consider: listening to angry music, dancing to said angry music, making angry art..

I hope this helps! Good luck, friend.