"Error calling registered function"

Hi…

I recently registered a function like…

registerFunction(excelOperations, {
name: ‘excelOperations’,
description: ‘Reads an Excel file and returns formatted JSON data’,
params: [
{
name: ‘file’,
type: ‘string’,
description: ‘Accepts a base64 encoded binary file’,
},
],
returnValue: {
type: [],
description: ‘Returns a Promise resolving to an array of objects representing the Excel data in a structured format’,
},
importPath: “…/functions/mailwizard/operations/excelOperations”,
});

& when I try to call it from plasmic studio , I get error …

cannot read property of undefined (reading, read)