Issue with Append Queries

Hello,

I'm using the Append Queries option for the first time as the tool I use to extract data can only export a certain amount of rows at a time, therefore I have two CSVs, one with time booking data for 2020, and one for 2021. I'm re-using the dashboard from another area which only used one file but I'm having some issues. Here are the steps so far;

• I imported another csv datasource (the 2020 file) and copy and pasted the transformations from the advanced editor of my previous csv into the new one which works correctly. 
• I click on the 2021 file (which the dashboard runs off) and go to Append Queries > Append Queries
• I select Two tables and in Table to Append I select the 2020 file
• I click OK
• When I look at the dates in the 2021 file there is no 2020 data, only 2021, so it looks like it's not appending the data. If I open each individually I see 2021 or 2020 data but no append is taking place. 

I've removed the append and re-done it but it doesnt seem to work. I dont want to append as a new table as I imagine I will need to re-create my dashboard and report references. 

Any ideas? 

One thing that does look a bit odd is the relationships view.

• Detailed Hours by... is the 2021 file I'm trying to merge data into
• DIR01 2020 Full_ is the 2020 file I'm trying to add in. 
• The relationships to Code Allignment and Rate Lookup are already there, but why is the 2021 file linked to rate lookup? Is it just because its inherited it from the append? 

Thanks

Chris