Logs:

00:00:00
Setup external network

00:00:00
Assigning external IP addresses

00:00:00
Setting external primary IP address

00:00:00
Setup management network

00:00:00
Management network setup - Skipped

00:00:00
Setup private network

00:00:00
Private network setup - Skipped

00:00:00
OS Template: Windows 2012 R2 Licensed

00:00:00
Start Converting template VHD

00:00:00
Template VHD path: C:Imagesw2012.vhdx

00:00:00
Converting to 'C:Hyper-VCustomerslamkk2019@gmail.comtest.testset.etestest.testset.etes.vhdx'

00:00:06
Error while converting VHD: Server was unable to process request. ---> Invoke error: A parameter is invalid. 'NOCIX-2-E5-2670C$Imagesw2012.vhdx' is not an existing virtual hard disk file.
Server was unable to process request. ---> Invoke error: A parameter is invalid. 'NOCIX-2-E5-2670C$Imagesw2012.vhdx' is not an existing virtual hard disk file.
at System.Web.Services.Protocols.SoapHttpClientProtocol.ReadResponse(SoapClientMessage message, WebResponse response, Stream responseStream, Boolean asyncCall) 
at System.Web.Services.Protocols.SoapHttpClientProtocol.Invoke(String methodName, Object[] parameters) 
at SolidCP.Providers.Virtualization2012.VirtualizationServer2012.ConvertVirtualHardDisk(String sourcePath, String destinationPath, VirtualHardDiskType diskType) 
at SolidCP.EnterpriseServer.VirtualizationServerController2012.CreateVirtualMachineInternal(String taskId, VirtualMachine vm, LibraryItem osTemplate, Int32 externalAddressesNumber, Boolean randomExternalAddresses, Int32[] externalAddresses, Int32 privateAddressesNumber, Boolean randomPrivateAddresses, String[] privateAddresses, String summaryLetterEmail)

00:00:06
VPS was not created

I can assure the VHDX is located in: C:Imagesw2012.vhdx, I even tried to open that directory on the server and it worked. don't know what is the issue?