Appending multiple approver names.

[S_Tran]

I have an approve document by multiple approvers flow that is currently working.  My intent was to have a column name "Approved By" and have all the names of the approvers listed in this "multiple line of text" column that I created.  The option on Sharepoint online "append changes to existing text" is not available.  I  know there's a way to use "append to string/array variable"  connector and also a way to concatenate the string.  Not sure which way is more efficient.   I'm unsure where to place them in my current flow.  Please see screenshot of my current flow.

[ScottShearer]

@S_Tran 

If your issue is that "Append text" is not available in the multi-line text box, you need to turn on versioning.  Once versioning is turned on, you'll be able to turn on "append text" in the list settings.

[S_Tran]

@ScottShearer 

Versioning is already turned on.  That was the first thing I checked. This is a screenshot of my Sharepoint online column settings.