What should I do if my 90-day report is still pending online before the due date?

For what it's worth - a personal visit (although tiresome) is still the most effective and responsive way to go. Queries can be explained, confusions can be clarified, issues can be resolved. The vagries of your local Immigration office become clear. As has been said many times, they are not all the same. Plus, the online systems, whilst admirable in intention, do not work for all situations. Often, courtesy and humour can go a long way in a personla visit.

Wait a little more. You did it Friday. I don’t think they work Sat/Sun and Mon/Tue where Government holidays I believe.

I've often made on-line reports that didn't get approved in the usual 3-4 days. I have then gone into the system and cancelled it, then immediately reapplied. They always then got approved within 24hours...

If you're going to go do a 90 day report in person make sure you go into the system and cancel the pending report.

Remember though you can file a 90 day report up to 7 days after your due date without a fine, SO really you have until the 17th before your report would be late