Okay. I got it to wor! Yay. Finally - but not with subtables - I gave up on subtables! I just used the tutorial below again (I had the output selected for one part that I shouldn’t). Thanks very much for your help.
Its great to finally see nested repeats 
Thanks very much guys - @guptast and @Sorry_Duh
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For the benefit of others 
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I followed the tutorial below.
With respect to Subtables I am not sure why it didn’t work? Even though I could see the ‘subtable’ showing in ‘Query Builder’. (by the way the subtable wasn’t originally showing in Query Builder, even though I have the foreign key setup correctly in MySQL, likely because the Database schema wasn’t refreshed as @George mentioned in his reply further above, but it appeared later on - I think after I did the refresh).
When I tested the query in ‘Query Builder’ the output didn’t show the subtable records, hence the nested repeat on the app side wasn’t working. I tried a few times and ensure the query were correct and couldn’t get it to work.
Regardless I achieved the same results using the nested repeat in Server App using the tutorial mentioned above.