Amos Fast toilet-tank cleaner – no longer at HSM?!

I was going to reorder a couple bottles because i thought it worked well, especially for hardwater and soap residue in our bath / shower! I only complaint was that it was not viscous at all, and they said it was thick and not going to run down, which I never found to be the case. That forced me to use more product than I should have, however I still found that it worked very well, even though needing to use too much it becomes pricey!
Why is it no longer available?