Google Business Performance API has a NEW API method that allows fetching multiple `DailyMetrics` in a single API request.
Review the deprecation schedule and instructions to migrate over from v4 reportInsights API method to Google Business Profile Performance API.

ErrorDetail

Details an error that resulted in a validation or internal failure.

JSON representation 
{
  "code": integer,
  "field": string,
  "message": string,
  "value": string,
  "fieldIndex": integer
}
Fields
code

integer

The status code, which should be an enum value of ErrorCode.
field

string

A path leading to a field in the request body. The value is a sequence of dot-separated identifiers that identify a protocol buffer field. For example, "errorDetails.field" would identify this field.
message

string

A description of why the field caused a failure. The message is in English and may not be suitable for display to users.
value

string

The value that failed the request.
fieldIndex

integer

If the request field that generated this error is repeated, this will contain the zero based index of the entry in that field which caused validation to fail.