How To Fix SFB509 - Selected element cannot be changed

SAP Error Message - Details

• Message type: E = Error

• Message class: SFB - Messages for Formula Builder

• Message number: 509

• Message text: Selected element cannot be changed

What causes this issue?

You wish to change an element in the formula (using double-click). This
function is not possible for the element you selected.

How to fix this error?

You may only change constants, character strings, or numbers in the
formula. To make a change, you must delete other elements and insert
the desired element.

Error message extract from SAP system. Copyright SAP SE.