You cannot post with transaction type & here

What causes this issue?

You have entered a transaction type which only updates depreciation
areas, which are not automatically entered in the General Ledger.
Therefore, no document can be created for Financial Accounting. In the
transaction you have selected, however, you can only post business
transactions with documents.

System Response

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

How to fix this error?

Via the menu bar 'Postings' and pull-down menu 'Miscellaneous', you can
post without a document. Alternatively you can enter a transaction type
which updates the depreciation area and has automatic entry to the
General Ledger.

Error message extract from SAP system. Copyright SAP SE.