Two addresses, so the right thing reaches the right place.
Zilda is small enough that all of these reach somebody who can actually change the thing you are writing about. There is no ticket number and nothing queued behind anybody else.
A receipt it read wrong, a claim form it would not fill, something that should exist and does not. Screenshots help more than descriptions, and the vendor and date of a receipt that misread is usually enough to find the problem.
What is held about you, a copy of it, or a request to delete it. Also the right address for anything you think this app is getting wrong about privacy — that is worth hearing about from the person who noticed rather than from somebody else later.
It goes to the same inbox. Nothing you type is stored on the way — the message is held for the seconds it takes to send and then forgotten.
If what you want to know is what Zilda holds and what it cannot see, the security page answers most of it without an email — including the one place where receipts do leave your own cloud, which is the part worth reading before you decide to trust it. The privacy policy is the long version, and says where every piece of it physically sits.