Hi @Sequeiros,M,Maria,JSHD1 R,
According to this article Supported column types, Multi-Line Text column with enhanced rich text is not supported by JSON column formatting.
Rich text fields return their values with HTML. List Formatting automatically escapes values meaning that these types of fields will include HTML in their text values and that HTML will not be used as part of the page. It is not recommended to use rich text fields with List Formatting.
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