(Ottawa) Canada’s Office of the Taxpayers’ Ombudsman (OTO) says it is closely monitoring complaints from people who say they have continued to receive collection letters from the Canada Revenue Agency despite the refund to the government benefits related to COVID-19 for which they were not eligible.

Francois Boileau’s office said in a Thursday press release that it continues to receive such complaints and will launch a “systemic” investigation if necessary.

The ombudsman says it’s possible that people discovered their overpayments from other sources, such as another government department, and then refunded the money without the knowledge of the CRA.

The Auditor General’s office reported in December that the federal government had paid out $4.9 billion in pandemic benefits to ineligible recipients, including wage subsidies.

It also found that an additional 27.4 billion in payments to individuals and businesses should be further investigated.

The CRA, which did not respond to a request for comment, has struggled to recoup that money, raising only $2.3 billion through voluntary refunds last December.