spots.

Do the brown spots look as though they are developing grey mould on them? If so, it's called Botrytis, and the only thing you can do is take off the affected leaves and 'segregate' those cuttings (or even destroy them, unfortunately) from any that are not showing any spots. Botrytis spreads by spores in the air from one leaf or cutting to the next, and if an affected leaf flops and touches a stem, the stem will also rot. The cuttings may be too wet and cool, this is the usual cause. Where are you keeping them? Are they too close together? You can spray the healthy remainder with carbendazim.

No there is no grey mould, the spot is making the leaf transparent, in the centr.
Nannydigit.

Keep an eye on them - you could spray them anyway to ward off Botrytis - which is usually fatal. Advice about keeping them dry-ish and well apart still stands, also be careful not to splash the leaves when you do water them.

thanks
nannydigit.