Black dots or marks on baby bib

I have this kind of problem with a similar material of bib too. Cld be due to the material of the bib or the milk powder itself. What brand of milk powder are you using? I didn’t try getting rid of it. I just bought new bibs since it’s not very expensive

This is black mould. Happens when cloth stays moist (including milk stains) for extended period of time. Try to hang dry wet items immediately even not washing it.. to remove it, bleach works

I found some dots on one of the clothes as well and wondered why!!

have to wash or soak inside water immediately after each use