I’ve got an Osprey Raptor rucksack that has developed some mildew spots on the straps and wais belt.

Is there anything I can use to remove it by either putting it in the washing machine or as a spray without it bleaching the fabric?

A bit of elbow grease and just fairy liquid and water works for me.

Sounds silly, but mild bleach solution and wash it well afterwards

Thanks for the advice, based on it I’ll try warm water, fairy liquid and a splash of Milton in the water.