+1(514) 937-9445 or Toll-free (Canada & US) +1 (888) 947-9445
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Super VISA templates

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But didn't submit marriage certificate... Is it mandatory

Maybe, the refusal is due to the agent. This time you should submit the application yourself. If your son PR or Canadian citizen, he should be able read the instructions and application guidelines to see what is mandatory.
 
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