How can a valid Canadian visa be deactivated?

A valid Canadian visa itself cannot be directly deactivated by you or by any outside source. However, there are ways a Canadian visa can become invalid:

• Cancellation by Canadian Authorities: If Canadian immigration officials discover the visa was obtained through fraud, misrepresentation of information, or if you become inadmissible to Canada for reasons like criminality or security concerns, they can cancel the visa. You'd likely receive notification of this cancellation.
• Expiry Date: All visas have an expiry date listed on them. Once this date passes, the visa is no longer valid for entry into Canada.

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