import requests

url = "https://api.diga.io/v1/project/{project_id}/member/{profile_id}/role"

payload = { "role": "admin" }
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.patch(url, json=payload, headers=headers)

print(response.text)

{
  "status": "error",
  "error_code": "CANNOT_REMOVE_LAST_ADMIN",
  "message": "Cannot demote the last admin in project 550e8400-e29b-41d4-a716-446655440000"
}