Hi,
Use RDBMerge add-in, it is very useful / fast and easy to use:
https://www.rondebruin.nl/win/addins/rdbmerge.htm
Before merging, change your sheet names temporarily to something like:
Cash
Cash2
Cash3
Then in the field
"Merge all files with a name that contains" enter the following name:
Cash*
There are many options which are self explanatory.
Regards,