How to ensure toilet cleaner blocks dissolve?

[zillah]

Hi Experts

I am experiencing this issue all brands of toilet cleaners block stuck in the cistern base although all of them are placed away from the water inlet

I have got 3 cisterns at home ,,,,please see attached video 

Is this normal ?

https://imgur.com/a/vm04L4K

Thx

[zillah]

Thx for the information learnt something new