I think the instructions for cleaning the filter by using water need to be revised. Shaking the bin with water in it then rinsing the filter under water doesn’t really work. In fact it simply wets the dust and makes it more difficult to remove from the filter. Several users have reported using another vacuum to vacuum the dust out - if done carefully this is a better way to clean the filter and doesn’t lead to pockets of dust becoming cemented to the filter after getting wet.
There is also no availability of spare filters (or any other spare parts for that matter) - in the UK. Plenty of 3rd party products with mixed reviews.