'We are committed to addressing the OCC's concerns because restoring trust in Wells Fargo is our top priority,' CEO Tim Sloan said in a statement.
The Dow Jones Industrial Average ends Monday in the red, its eighth day of losses in a row and its longest losing streak since August 2011.
Stocks are mixed on Monday as Wall Street shakes off worries over the way forward for the Trump White House.
'We've embedded security into the design,' a Wells Fargo executive said. 'There's a lot of layers of security around the application itself.'