Resize VM A0 basic to A1 basic

Regards,

We have a virtual machine that has run out of RAM memory, we need to increase from a basic A0 to A1. We want to make this increase, but we are afraid that we lose the information stored in the VM, as I read we can lose all the information of this VM. 

Our disk is a standard HDD of 30 GB and this disk is safe on group resources

Thanks for the help