I received a mail from CRA saying GST/HSTC cannot be calculated without " world income, for the period in 2020 before you came to Canada" What should be my next action?

[JEM0179]

You should provide CRA with this information. If you were employed use your payslip or your payroll information to calculate this amount and then convert it into Canadian dollars using the bank of Canada conversion rate. 

Kindly see below for additional information.

TurboTax FAQ: GST/HST Information 

Bank Of Canada: Exchange Rate 

TurboTax article: Do you need to declare income earned from sources beyond Canada?

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