How do I access my previous posts under 'Author'?

It seems only your question from November is showing, besides this post.

Could it be that you used a different account for the questions from last week?

Could it be that the forum acted up last week, and it didn’t actually submit? [You should have seen your own post after making the post, as confirmation.]

Or perhaps the forum is still acting up, and not working properly yet?

Here’s a thread from February 28–March 8, which should have been listed for you: Restoring a deleted app on my iPhone 11 backed up on iTunes - Apple Community

(Found through Google)