You may also be entitled to reimbursement of your extra expenses. Here is United's we page explaining the EU261 laws for carriers operating in and out of the European Union. https://www.united.com/ual/en/us/fly/travel/destination/international/eudenied.html
I have just received compensation from a European carrier for cancelation in July 2023. I received full reimbursements of 2 nights of hotel and meals. The first claim was only partially reimbursed, but a polite email asking from reconsideration got me my additional out of pocket. As noted, I had to submit all receipts.
My plane's tech issues had to do with a bird strike which is considered extraordinary so not due the 600 (or more) compensation. I have been advised to dispute that as my flight was on a successive day like yours. I haven't decided whether I will push farther or let it go.
There are companies that will file and fight for you, but they take a cut (of course) of any money. Google if you wonder about that route.