A man with Parkinson's disease was bed-ridden for the last month of his life because specialist equipment was not provided by his council, a report said.
Occupational therapists recommended Lancashire County Council give the man a special chair, the Local Government and Social Care Ombudsman said.
However an investigation found the council had taken too long to approve the unnamed man's funding application.
The council said it had "apologised fully to the family for the distress".
A spokesman for the authority said it had "drawn up an action plan to address the shortcomings identified".
The report said he could no longer sit in a standard chair because he was at risk of sliding to the floor.
His wife was unable to help pick him back up because of her own health problems.
But, seven months after two separate occupational therapists made referrals for the special chair, it still had not arrived by the time of the man's death.
His wife complained to the council and the ombudsman and said she was given "mixed messages" about the reason for the delay.
The ombudsman's investigation found the council delayed requesting the specialist chair, failed to record its contacts with the contractor who would provide the chair, and took too long to approve the funding application.
Ombudsman Michael King said: "While the council had already apologised before my investigation, it failed to identify the root cause of the delay.
"When things go wrong, lessons can only be learned to improve future services if the correct causes are identified."
He said the council had paid £750 to the man's wife for the distress caused.