A mental health hospital charity has been told it made "repeated and systemic failings" in its leadership by health inspectors.
The Care Quality Commission (CQC) raised several concerns at St Andrew's Healthcare, based in Northampton.
They included a two-year backlog to address issues found by the CQC in previous inspections.
St Andrew's Healthcare said it had new leaders who were committed to making improvements.
Kevin Cleary from the CQC said: "These failings hindered the ability to provide safe and effective care."
St Andrew's Healthcare treats up to 900 mental health patients in Northampton, Birmingham, Nottinghamshire and Essex, with 90% of referrals from the NHS.
The CQC inspectors, who visited the charity's headquarters on 23 and 24 October, found the use of physical restraint had increased despite a plan to reduce it.
They also found the process of telling a patient's family when something went wrong was "not fully effective".
They noted in their report an employment tribunal found a member of staff was unfairly dismissed because he had been a whistleblower at a previous workplace.
The inspectors also found staff were not always confident to raise concerns without fear of reprisals.
The report said senior leaders had "not fully accepted the serious nature of concerns raised" by the CQC in previous inspections, causing a two-year backlog to address patient safety issues.
Mr Cleary, CQC deputy chief inspector for mental health and community services, said St Andrew's Healthcare had "processes that supported good care".
But he said: "There were also repeated and systemic failings relating to procedures and clinical governance."
He said the management at the charity "had comprehensive knowledge of challenges faced, but many of their plans were in their infancy".
St Andrew's Healthcare said: "Cultural change can take time, especially in a complex mental healthcare setting."
The charity said it had implemented changes to its restraint, seclusion, and long-term segregation processes following a review.
A spokeswoman said: "We have a new leadership team in place who are committed to making improvements and creating a culture of complete openness, honesty and transparency."