Hi everyone ! My old boss produced a false T4, with an amount I’ve never received (and never produced payroll document). What should I do ?

You should contact the Canada Revenue Agency (CRA). If you are in Canada or the United States, you can call the CRA at 1-800-959-8281. If you are elsewhere, you can call 613-940-8495. This page has more ways to contact the CRA: Contact the Canada Revenue Agency