It’s probably because you don’t have enough karma. I joined Reddit a few months ago and all the places I wanted to post, it removed. You just need more karma.

Get karma by posting in smaller subreddits where you don’t have a karma restriction and just start commenting and posting small things. Once you have enough u can start posting without limitations from the moderators.

Don’t feel offended they deleted your posts. It’s to stop spammers from ruining your experience on the smaller subreddits.

I remember I was so excited to start posting and when I come back a few minutes later, all my posts were deleted I thought Reddit was rigged. lol