Is It OK to Keep Wearing Cracked Invisalign Tray?

I would recommend asking your invisalign doctor, but here are my thoughts. If the crack is not that bad and you can still wear the invisalign tray then I would keep wearing it until day 14.
If the crack has completely spilt the tray such that it is unwearable, and you are on day 11 of day 14 and have been wearing for the proper 21-22 hours a day, I would go to your next set of trays. Your teeth may be sore for a few days, but as long as you were wearing the old tray at least 21-22 hours a day, it should be okay.
I hope that this is helpful!

Ideally, aligners are worn for 14 days.  However, if one cracks on day 11, one can often simply move on to the next aligner with no significant change.  If it happened on day 2, then a new one likely would be best, so wearing the previous aligner until the new one is made is the normal treatment.