Expression evaluation error at function a!queryEntity: An error occurred while retrieving the data

Hi

my query is working fine for the last 9 months and now it is showing errors as below:

Expression evaluation error at function a!queryEntity: An error occurred while retrieving the data. Details: Unexpected error executing query (type: [DetailViewDT3872], query: [queryentity expression], order by: [[Sort[AccNumber asc]]], filters:[null]) 

I built a new constant and it still did not work.

Could you please assist why it is starting to show this error and how to fix it?

this is my query:

a!queryEntity(

entity: cons!Detail_View,

query: a!query(

selection: a!querySelection(
columns: {a!queryColumn(field: "AccNumber")}
),

pagingInfo: a!pagingInfo(
startIndex: 1,
batchSize: -1
)

),

fetchTotalCount: true

).totalCount