IB, earlier, had posted a bulletin in TWS. This morning at the open, I had no bid/ask for ES, YM, NQ. Caused me to miss a huge opportunity.
Had the same problem with IB today. No bid/ask for YM and then ES shortly after the open. Orders did not execute. Issue was resolved about 20 minutes after the open. Everything working fine since then.
Such an event should be a reminder for everyone that one or more backup accounts at another broker(s) are essential. At least if you trade more than 1-lots.