Hi Madhu, thank you for bringing this to our attention. We're sorry to hear that the replacement rain cover you received appears to be the wrong size.
This certainly shouldn't have happened. Could you please email us at help@viaterra.in with a few pictures of the rain cover fitted on your Fly Magnetic Tank Bag, along with your purchase details? Our team will assess the issue and help you with the appropriate resolution.
Regards,
Team ViaTerra