Thanks for the replies Richard
1) Yes, I understand that you are unable to turn the power off now. You have a few options here when you are able to check things out.
2) When you have daylight tomorrow, I would turn the main breaker to OFF and completely remove that breaker and re seat it. Then see if everything is back working OK. Since the breaker has 2 separate switches, that is called a mini or a tandem breaker.
3) Another option would be to determine if the trouble follows or goes away by "rolling" the circuit. You will need to find another breaker of the same amperage, ie, 15 or 20 amps within the panel. Temporarily remove the existing hot conductor from a known working breaker of the same amps as the one you are having problems with and temporarily terminate the hot wire from the suspected breaker over to a known breaker that works correctly. If the trouble follows over to the relocated breaker, then you have a wiring issue or loose wire or splice somewhere in the circuit. If the trouble goes away, then possible that the original beaker is faulty and needs to be replaced or that breaker slot is causing the problem due to a fault on the hot bus bar stab.
3) Another option would be to purchase a replacement breaker and relocate the 2 circuits to another spare slot in the panel (although since you are already using tandem breakers, you may not have a spare slot).
Hope this helps.........If you have any additional questions, let me know and I'll be glad to answer them for you.
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