We had to cancel a June trip to Greece and The Netherlands scheduled for my husband, daughter, and myself from June 14 to July 5 due to some health issues. Our Chase Sapphire Reserve card provided reimbursement for airline and hotel penalties (about $1,700 total), but they do not reimburse for tickets to attractions. While the amount (about $83 each) wasn't that great, I wanted to file so I could learn what the process was like and whether our claims would be approved.
Our daughter had a one trip plan, and my husband and I have an annual plan, all through Allianz. The process was a bit of a pain, but I eventually figured it out. You need to fill the complete claim form in one session--I couldn't find a way to save and return. However, you can return to upload all of your supporting documents.
Our daughter's claim was approved and the reimbursement was in her bank within one day.
Ours took a little longer because they decided to send us a check for some reason, but still it was only about a week until we received the check.
I hope this is helpful. If you are interested in our experience with Chase Sapphire Trip Cancellation, my report on that process is here:
https://community.ricksteves.com/travel-forum/budget-tips/recent-positive-chase-sapphire-card-trip-cancellation-experience