When the Page Will Not Open
"Crown is down" is the most typed phrase in this corner of the net, and it is usually wrong. A dead mirror is not a dead market. The market sits behind several addresses, and one of them refusing to load says very little about the others.
First: is Tor itself working
Open check.torproject.org in the same browser you are using for the market. If that page will not load either, the problem is not Crown. It is the connection underneath, and no address on any list will fix that until Tor itself is moving.
The address
Before you blame the market, check the address one character at a time. A single wrong letter puts you on a different site that looks like this one, with a login form ready to take your password. Run the pass in the character check before anything else.
The three mirrors
If one mirror will not open, the other two are still the same market. Nothing is lost by switching. Here are the three current mirrors:
A queue that stays a queue
The first thing you see after the address loads is a queue: a walking figure and a line that says estimated wait under a minute. If that queue does not move, the circuit is stuck. Build a new circuit, restart Tor Browser, or move to another mirror. A stuck queue is a stuck route, not a closed door.
A blank page that loads
Sometimes the page opens and is empty. Do not hammer the reload. Give it a moment. If it stays blank, the fix is usually a fresh circuit. The page loaded, so the address is resolving; the content is what is lagging behind.
When the market really is down
If all three mirrors refuse to answer for hours, the market is genuinely quiet. That usually runs in days, not weeks, and while it is quiet the address in your bar is still yours. The silence is on the market's side, not yours.
If the problem is Tor Browser itself, set it up from scratch.