Hey there, steven.lepper.
I've checked and verified that we have reported issues with other users when trying to print to reconciliation report in QuickBooks Online for Mac. We've already submitted a ticket about this issue and our engineers are all hands on deck working together for an immediate fix to sort everything out.
If you haven't contacted our QuickBooks Online Support, I'd suggest doing so. They can add your account to our lists of affected users and any progress will be communicated via email.
In the meantime, you can try accessing your account using another supported browser.
In case you want to know some "How do I" steps in QuickBooks Online, you can always visit our Help Articles page for reference.
I appreciate your patience while we're working on this. If you have any other issues or concerns, please let me know by dropping a comment below. I'm always here to help. Have a lovely week ahead!