I believe I have found a bug in the data import and update process. Let’s consider a spreadsheet to be imported with the following fields: ID, Name, Phone, and Password. Imagine that, in some rows, the Phone field is not filled in. During the first import, the records with the Phone field left blank are imported correctly. However, when performing a new import, for example, to update the Password data, an issue arises. The CRM interprets the blank Phone fields as new records, duplicating the existing entries. In other words, if there is a blank field in the spreadsheet, that record will always be duplicated during the import.
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