Probelms with appending data with power query

I would be grateful for some help.
I wish to combine 2 tables with the same headers on different worksheets into a single master worksheet ( I have enclosed a sample worksheet to show the problem).
I have created a query from each table and then run an append query to combine the two to a new worksheet. The query runs without problems but the first column of the appended table show as null. I cannot understand why and need soem assistance to resolve.
Just for background the data is entered into this via a user-form into the original table and I did not know if this made any difference.
Thanks for any advice.

a password would be handy

If I create a new workbook then this procedure work fine but the workbook I am using is part of a much bigger project so starting again would be very time consuming for me.

AliGW, thank you.
Simple mistake by me! Resolved.

As an alternative; you can try the macro in the attached workbook which is saved in the same folder with "SATxest v4.2.xlsm"

Note: I tried to post the code, rather then attaching the file but the server responded with a fake error about "SQL Injection" which was not the case, actually.

Sample file is attached.

The query removes the last row in the master sheet rather than combining the 2 tables.
Have I missed something?

Sorry - wrong version attached. Try this one.

Works great. Thanks