Dough too sticky to form

Hey! I've mixed 100g active starter, 350ml warm water, 500g ap wheat flour and 10g salt.

I've done 3 rounds of stretch and folds and two of coil folds (all done 30 mins apart). The dough came out of the bowl beautifully but it's so sticky and soft I can't form it.

Does anybody know a solution to that?