php: problem loading images through dropzone VUE.js

For no apparent reason, my site returns the following error when I upload an image:

enter the description of the image here

The message says:

DOCTYPE html>


    
    
    
    

Component spfx dropzone

I'm using the load sample of the sample react-file and in and uploading I am changing the metadata of the file. The problem is that it works when I'm testing and when the application is implemented it does not work anymore. The file is loaded but not the metadata.i receives the 404 error that the file can not be found.

sending: function (file, xhr) {
be _send = xhr.send;
xhr.send = function () {
_send.call (xhr, file);
};

myDropzone.on ("complete", function () {
console.log ("enter metadata");
pnp.sp.web.getFolderByServerRelativeUrl (_parent.props.folder) .files.getByName (file.name) .getItem (). then (item => {

item.update ({
OData__x0074_ag1: _parent.props.Tag1,
OData__x0074_ag2: _parent.props.Tag2

});
})
console.log ("entering metadata facts");
})

}