Hi partner,
You may have entered a value that does not match the field data type and format.
When you open a field's settings interface, you'll see its Data Type and other formats.
All the data you enter in Excel must match the format of its fields.
For example, if the field is Single Line of Text and the Maximum Length is 160, then all values in this column in Excel cannot exceed 160.
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If the field is Whole Number, the Maximum Length is 1,000,000,000 and the minimum value is 0, then all values in this column in Excel can only be integers and they must be between 0 and 1,000,000,000.
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The format of these fields can be seen on the downloaded Excel template. When you click on the cell, it will display the format requirements of this cell, so the data you input needs to meet this requirement.
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So, I recommend you use an import template or export a view as a static worksheet.
1. import template
Go to Advanced Settings > Data Management > Templates for Import, select the entity, download the template, enter the data in it, import it.
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2. export a view as a static worksheet
Go to the view, click Export to Excel > Static Worksheet, download the Excel and enter the data in it, import it.
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Finally, please pay attention to the language. If your environment is set to English, you can only type in English in Excel and you cannot enter any text in other languages.