limitation when sharing HD video on Vimeo

When I want to share an HD video 720p on Vimeo, If my video exceed 5 minutes, I receive a message that tell me that my video is to big to be shared on Vimeo => ?

So I'm limited to share HD video 720p less than 5 min.

I don't know from where comes this limitation and what to do to remove it.

P.S. : I have a basic account on Vimeo which include the possibility of sharing an HD video / week

This problem comes even if it's my first video sharing of the week

Thank you in advance

Best Regards