I recieved Notice of Reassessment saying to pay 4000 dollers , the paraghraph say " we did not recieve the GST/HST returns we requested."

If you have a business and had a GST number, you would have had to have a business account and file an HST/GST return.  If that is not done, it is something they would request you to do if you had a business with a business number and GST number. Contact the CRA by phone at 1-800-959-8281 so that they can assist you further.

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