Someone near to me has received an Interac transfer from an unknown person.

Here's what we know: It's a repayment scam (unless we later figure out it is legitimate by realizing who it's from and what it's for, but we don't think so.) So, we don't need basic advice on that, we already know once someone comes to say "repay me," that we just block and ignore that person.

But regarding the initial transfer itself, what is our course of action? Obviously, don't touch or spend the money. But what else? Should we just ignore it, or must we proactively call the bank and explain that it is unknown to us? This bank always keeps us waiting 40-60 minutes on the phone so we're trying to see if we can avoid that.