hello my car vauxhall astra convertable does not have the vin plate how do i get a nother one

Hi David, that's quite an unusual problem. You would have to contact the DVLA and request a replacement. 

They will probably require proof of vehicle, also you should find that the vin number is stamped into the floor pan just inside drivers footwell. There should be a plastic strip in the carpet, if you lift this there should be a vin number for the car. 

Hope this is helpful.

Regards Andy.