Auto Number or Sequential Numbering for Forms

I do something similar to this all the time in a workflow utilizing the ID field from the list or library. A sequential, unique ID is generated in the list or library for each item created.

Here is one way to accomplish this via workflow:

1, Configure a workflow on the list or library (possibly configured to start when an item is created).
2. Add and configure a “Build string” action at the beginning of the workflow.

• Text = AA2023-{ItemProperty:ID}
  →   The “AA2023-” text is entered as your static prefix.
  →  {ItemProperty:ID} is added from the Item Properties tab via the Insert Reference button.
• Store result in = txtRequestId (text variable named whatever you want)

3. Add and configure an “Update item” action to update the item with the variable.

• Update = Current item
• Field = Request ID (or whatever your list column is named)
• Request ID Equals Workflow Data txtRequestID

4.. This will update the list column with a custom, unique Request ID for each item created (AA2023-1, AA2023-2, etc,).