How to disassemble Macom VAC5090 vacuum machine

My Macom VAC5090 vacuum machine has become non-operational because one of the handles, that help secure the bag, does not lock anymore.
I tried disassembling the machine by removing all the screws on the bottom, but it does not open. I have looked for hidden screws, but found none.
How can I disassemble it? It has been operating for two years only, quite seldomly. it would be a pity to have to dispose of it!
This is how the machine looks: