Error uploading file to Back-end Media Manager

I am trying to upload a file (simple .jpg image of size 240kb) to Media backend using upload button and a function in .jsw module where code is directly copied from Corvid API reference guide for upload method ( ) , but it fails with an error in Console log :
“406 - {“error_code”:-7751,“error_description”:“Failed to get image info.”}”.
Can anyone help me a suggestion why this error appear ?

Thank you !!

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How are you doing this? How do you call the .jsw module?

Hello Yisrael,
On the front end I use upload button to select the file from my PC and normal button where on click I trigger following call to backend:
export function button1_click(event) {
if ($w(“#uploadButton1”).value.length > 0) {
It seems to be wrong , but how should I do this ?

Best Regards,