VMWare ofv export not working

Hi Guys,
I am using VMWare ESXi Hypervisor 6.5.
I created an ovf template and imported 2 number of machines from that template.
Now after some configuration, when I am trying to export one of the machine, my export is getting failed after downloading 15.6 GB of vmdk file.
I tried export with ovftool as well, it shows the command is completed successfully, but it only created vmdk file not .ovf and .iso file.
Has anyone faced this kind of problem?