Bell has apologized after it incorrectly made a time change on some customer smartphones.
The company says there was an issue with its system that caused the change, which has now been resolved.
Customers complained on social media about disruptions to their mornings because of the error.
The company says users may need to restart their device or briefly switch their smartphone into airplane mode to fix the problem.
Bell spokeswoman Caroline Audet says the company thanks everyone for their patience.
Daylight time is scheduled to end on Nov. 7 when clocks are set back one hour.
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