Sprinkling water over impurity to purify it

Q: In my pregnancy I've been getting clear or yellow discharge very rugularly.

So sometimes if I'm out and I have slightly more than a Dirham size then I just sprinkle water over it and try to scrape it a bit but it's always wet, not dry. So sometimes I can't wash and change my underwear when I'm out.

Does sprinkling water over suffice?

It worries me because of my wudhu and salaah and it's validity.

Supplier putting a condition that a sale cannot be cancelled once an item is ordered

Q: My supplier sends me pictures and specifications of items that he is selling via WhatsApp. Whatever items I want, I order via WhatsApp. Is it permissible for my supplier to put a condition that once I order an item, the order cannot be cancelled, or is stipulating such a condition zulm (oppression and extortion)?