The "level of stress" on an NHS ward may have contributed to a man's death, an inquest heard.
Matthew Arkle, who suffered from schizophrenia, took his own life after leaving Wedgewood House in Bury St Edmunds, Suffolk, without an escort.
The inquest heard that staff were "so busy" there was a delay in reporting the 37-year-old missing last April.
Norfolk and Suffolk Foundation Trust (NSFT) said it had since made "improvements" to services.
Mr Arkle, who heard voices in his head, was diagnosed with paranoid schizophrenia when he was 20.
The inquest heard he was admitted to Wedgewood House in February 2017 after taking an overdose. Three months later, he was allowed out on unescorted leave but was found dead just two days later.
Mr Arkle's mother Sheila previously told the inquest she had asked for his leave to be denied because his family would not be around to support him, but this had not been communicated to staff.
The jury also heard that the "level of stress" experienced by staff at the unit, in the grounds of the West Suffolk Hospital, meant they did not immediately realise Mr Arkle was missing.
Charge nurse Stuart Clarke told the hearing the mental health unit had been "extremely busy" when Mr Arkle disappeared and there were "a number of alarms going off".
Speaking after the inquest, Mr Arkle's sister Jenny said the family had been "devastated" by his death and believed a "number of errors" had occurred.
Recording a conclusion of suicide, coroner Nigel Parsley said he would raise a number of concerns with the NSFT, including its record keeping and the information given to staff during shift handovers.
In a statement, the trust - which is in special measures - said it had carried out "a detailed review to learn as much as possible from Matty's passing and to implement positive improvements in services".