There are a few possibilities.

Shadowbanning is a Reddit feature where you can see your comments, and mods of subreddits you post in can see them, but nobody else. Mods can manually approve it, but usually won't (in part because they won't usually even see it unless they happen to stumble across it: it's not displayed anywhere for them to check). If anyone other than you tries to go to your profile, it will appear as though your account does not exist.

Automod is very popular. It can remove things based on keywords or phrases, based on the age of your account, or based on how much karma your account has. If automod removes something of yours, it is the same as if it was manually removed by a mod. It will be visible to you, but anyone else browsing the thread will just see "[removed]". However, your account page will still be valid. The redesign might have changed things, but on classic reddit, comments removed by mods or automod will actually still be visible on your user profile, even to other users. There is the option for mods to reply letting you know something was removed and why, but with low karma limits they usually won't do this, because part of the point is to kerb spam, and letting spammers know they're not getting through defeats the purpose.

A third option, probably not happening here, is removal by Reddit's Anti-Evil Operations. This is at least ostensibly manually-reviewed, so if your stuff is removed instantly it's probably not this. Things removed in this way will not be visible to anyone, not even mods. I believe you'll receive a message from the admins letting you know, but I'm not sure. AEO has a habit of making really bad calls, like removing obvious jokes or idioms that just happen to contain one or two words that, in isolation, could look like threats.