Uploading Documents

[Splendude]

Advice needed. Regarding Gatehub:  My documents (passport and bank statement) are not being accepted.  I resized them to get them into the pixel range and they are also now only about half a MB in size - still perfectly clear and legible and in colour as stipulated.  However, as soon as I click on Upload, I get a message at the top of the screen saying 'Identity Error'.  What does this refer to?  I've submitted a number of requests for help on Gatehub's Support Page, but only get automated responses telling me about the size of documents accepted.

What can I do?  Any help will be much appreciated.  Thanks.