Hi @pwaab,
By default a Text Box control will have a default value within the 'Value' property. You can remove this value by only leaving empty double quotes which is shown below:

The text within the value property will otherwise have to be manually removed by the user. In case you only want to provide a placeholder text, you can leverage the 'Placeholder' property. This placeholder will only appear in case of no value input and instantly disappear as soon as the user starts writing.
In case of a Form DataCardValue (in Edit mode) make sure that the linked record does not accidentally contain Text Box as column value. It may be beneficial to check whether the DataCard container does not accidentally contain a manually added Text Box control in addition to the DataCardValue.
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