Welcome back to planDisney, Nathalie. I'm glad you brought us another question!
I am sorry to hear you had to stop
Magic Key payments due to financial issues. Life can have many ups and downs, and I understand wanting to visit
The Happiest Place on Earth throughout them. While you'd need to pay any past due amount on your Magic Key Pass to renew or purchase a new Magic Key in the future, you should be able to buy a
standard theme park admission ticket. The theme park reservation calendar for the Magic Key and regular tickets are separate, so making a reservation for a new ticket should be no problem (subject to availability).
Nathalie, if you have more questions about your Magic Key, or want to discuss your situation with a Cast Member, you can call the Magic Key Monthly Payment Guest Services Line at (800) 410-4656. You can also visit the Disneyland Main Ticket Booth if you're local and it would be easier.
I hope this information helps, Nathalie. And I hope you visit us again in the future!
Magically yours,
Melissa