Urgent! Help needed! for troubleshooting a Power Automate Error.

Gopal, Amarnath 0 Reputation points
2026-06-30T21:03:51.5466667+00:00

Error: "OpenApiOperationParameterValidationFailed. The 'inputs.parameters' of workflow operation 'Create_item_-_add_to_master_list' of type 'OpenApiConnection' is not valid. Error details: The API operation 'PostItem' requires the property 'item/field_66' to be a string of maximum length '255' but is of length '439'."

My flow is running into the above error when it triggers the 'Create item' action which populates columns in a share a point list and it's doing that for multiple columns for the same reason/error. I have updated the respective columns from single line to multiple line text through the SharePoint site list settings; however, I am still getting the above error at every iteration of the flow.

For context, this flow uses a Qualtrics API to gather the collected data from the Qualtrics forms/survey that people fill out and then populates the entered data into respective columns in a SharePoint list.Error 1

Error 2

Microsoft 365 and Office | SharePoint | Other | Windows
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  1. Kai-L 18,970 Reputation points Microsoft External Staff Moderator
    2026-06-30T21:55:32.61+00:00

    Dear Gopal,

    Good day, and thank you for the detailed description of your issue.

    As a forum moderator, I genuinely wish I could directly access your Power Automate flow or step into the backend systems to diagnose and resolve this for you. Unfortunately, my role here is limited to providing general guidance and solutions that you can apply from your side.

    Based on the screenshots and the error text, Power Automate is still treating the SharePoint columns as Single line of text, even though you have already changed them to Multiple lines of text on the SharePoint side. This typically means that the Create item action in your flow has cached the old SharePoint column schema. To resolve this, you can try switching the list in the existing Create item action: first, select a different list in the action, wait for the screen to refresh, and then switch it back to the original list. This should force Power Automate to reload the column definitions and pick up the updated Multiple lines of text schema, without having to delete or recreate the entire action.

    Also, as this forum primarily focuses on Office 365 products and their native features, I highly recommend reposting this in the Power Platform Community, specifically under the Power Automate forum. This space is actively followed by Microsoft MVPs, platform developers, and experts who regularly work with power automate flow issues. Beyond standard troubleshooting, the forum provides access to a vast repository of community-tested templates and deep-dive technical documentation that addresses complex issue. Participating in this forum can also be a great opportunity to learn from experts and further refine your approach.

    I hope this information helps clarify the situation and provides you with practical next steps. Should you have any further questions or need additional assistance, please don't hesitate to reach out. I'm always happy to help.

    Have a wonderful day! 

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