I guess it depends. My understanding is, parents are also finding it hard to balance their work (from home now) with taking care their kids, in many cases it also influences their production.
In your case, obviously not your fault but, you do not have their kids in care and also your expenses are reduced (food, water etc).
My suggestion would be to discuss with them and negotiate. But, if they can't pay then there is absolutely nothing else to do. It's a very challenging situation for everyone.
As they mentioned hopefully the government can help us out somehow.