Hi @Ladislav Zelinka,
Based on my research and testing, please try to do a troubleshooting: check if the column name has changed? If you change the column name, it keeps the old name in the background, so the "field name" should be the original old name.
In addition, if you need to insert a hyperlink through SOAP, please refer to the following format:
<Field Name='Test'>https://www.yahoo.com, Description</Field>
Hope it can help you. Thanks for your understanding.
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