Patio/Drive mould/algae etc. (no replies)

Can anybody recommend anything for this please? I was told that Sodium Hypochlorite does the job, but there seems to be several options for different products. Just found a half-used Wet and Forget in the shed and don’t remember it being a success, but I was probably using it incorrectly knowing me.

If anybody has found one that works, I’d be grateful.

TIA.