A single Google Sheets document can hold maximum 2 million cells. Your connections will fail if the amount of new cells you are bringing in with an update will exceed these 2 million cells.
To prevent connections and updates from failing, please ensure that the destination spreadsheet has enough free cells to allow the update to succeed.
To reduce the amount of cells used inside a spreadsheet, remove any cells, ranges, columns, and sheets that you no longer need (obsolete) or that don't contain any data (blank). Moreover, use a filter or query to only transfer the data that you need.