A woman accused of robbing a bank in downtown Bangor this summer pleaded not guilty today – but is expected to change that plea next week. 25-year-old Matisha Pitts has been held without bail since her arrest, pending a mental health report. A federal judge found her competent to enter a plea today, based on that report. Pitts is now scheduled for a change of plea hearing November 17th.Court documents say in July, Pitts handed a note to a teller at the Bangor Savings Bank on State Street. The note said Pitts had a weapon and demanded money and if any tried to stop her, she’d start shooting. Police arrested her a short time later in an apartment on Kenduskeag Avenue.They say she had around 8-hundred-dollars in her purse but no weapons.If convicted, Pitts faces up to 20 years in prison.