The charity IHC is investigating a complaint from an elderly woman who says she felt pressured into donating.
The case has raised questions about commission-based street fund-raising by charity agents.
Peg Jacobs, 80, says she made it clear to a street fundraiser that she didn't want to sign up to direct debit donations, but says she felt trapped and intimidated and ended up signing.
IHC says complaints are rare, but it's asking its agents to review how they approach people for donations.
It contracts some fundraising to Australian-based agency Cornucopia which says the application was never processed.