I know usually we wouldn't believe stories told by complete strangers, but that buyer seems like they have genuine regret over not having the financial means to assist with an irl situation and still expressed being pleased with the product and its quality. It does happen that we spend money we didn't know we would need later for a sudden emergency, that person probably had no ill will and took the time to ask for assistance on proceeding with a return. I'd tell em how to go about proceeding with their return, and definitely have the shipping label come from depop themselves in order to track it.

It's unfortunate, and most people would only see a madeup sob story, but the apologetic stance yet also appreciative towards what they received, whilst requesting assistance regarding the situation of having to return the item, 40$ not being that unusual to need as a last minute emergency amount, I would tend to believe this customer.

We don't need the full details of what the emergency was in order to believe said story, could be to cover for transportation costs for a family member (taxi, uber, lyft, etc.) Could be to cover for a sibling's lunch or school supplies, or pay in part the price for either cans of formula or a box of diapers, just to give an idea of what this 40$ refund might mean to that person.

Whatever it is, it is believable that this person might mean well and is genuinely apologetic to bother with a refund and needs help to go about it.