How to disassemble Tefal Access Steam+ Model DT8100?

Hello,

This device turns on just fine but does not release any steam. It seems like it's clogged with calcinated stuff. I tried pouring a 1:1 mixture of water and vinegar in the head opening which helped remove some of the calcite but it still didn't work. I need to disassemble it to clean deeper. I tried removing all the screws I found (6 screws, two at the bottom, three hidden behind the water tank, and one hidden behind a rubber plug in the head) but I couldn't pry it open. Anyone know how?

Thanks in advance!