I'm using TurboTax online.
In response to similar requests, TurboTax experts have advised to override with zero income in Box 26. Not a complete answer.
TurboTax is incorrectly downloading Box 26 from CRA into TTax Box 26 for Communal Income, not TT Box 26 for Investment Income. So the correct advice to your users to overcome your coding error would be to delete TTax Box 26 communal, and manually re-enter into T Box 26 for Investment Income
