My sim refuses to do laundry, but others will do it just fine

@AsteriaXilfaren , Amish Vampires!!!🤯 Now there is a twist! 🤣

So, can she still do the laundry at night?  🤔 Since she is a Vampire without Sun Resistance, I can only suggest 3 things:
1) try moving the wash tub and clothes line inside (don't know if this will work, but it is worth a try in your case)
2) get her Sun Resistance as soon as possible
3) cure her of her Vampirism. 

Other than that either she will have to do the laundry at night or other Sims in the household will have to do that chore! 😉