You need to provide some more details, without that it will take much longer to troubleshoot...
E.g. Detailed log of backup job, details about the backup policy using bppllist <policyname> -L , VM details (total data, snapshots size/number, etc.)
Hi, please provide more information such as :
1. is this the 1st time taking backup of this VM?
2. If this is not the 1st time, what was the previous image size? bpimagelist will give you this information
3. If this is the 1st time, what is actual use space vs free and total capacity of the VM. Not the Datastore size.