Hi,
I came to the same situation in my environment recently where ESXi attached HP MSA storage restarted due to sudden power loss.
2 out of 4 LUNs were disappeared from the ESXi host and becomes visible in available list.
Run the command
"esxcli storage filesystem list" if it show an unknown vmfs version for the LUNs which are not visible on the esxi host.
Below are the steps to resolve this issue.
esxcli storage filesystem unmount -u "UUID" (where write the impacted/invisible LUN uuid).
Now you will be able to see this in inactive condition in the esxi host.
but still you are not ok, you can not mount this it will give you an error.
Get a graceful restart of the storage once.
Then, once storage comes online, try to mount it from Vcenter and if still fails, try to unmount from ESXi directly by logging on vi client then try to mount it from vcenter.
It resolved mine issue, hope it will resolve yours too.
If find this helpful or solves your query, do not forget to mark it.
Thanks,