when is the deadline to apply for training as examiner?

Question

I was on the process of applying for training as examiner in chemistry.I had even not finished uploading my documents. The application status was rejected due to lack of experience despite the deadline been not yet reached.

I have an experience of more than 13 years of teaching and examining chemistry.I really do not understand the reason for rejection of my application.I been waiting for this chance far too long. Kindly reconsider my application.

Thanks in advance