As per the following answer provided on the forums:

It asked to create hosting addons on SCP as well as configurable options in WHMCS then you need to create a link or association as per the attached screenshots…

All those setting were done properly and with caution however once client order is auto provisioned (VPS) unfortunately he gets the Default Hosting space specs (CPU, RAM, HDD, IP, Snapshots etc..) none of the hosting addons/upgrades were available for him. at the point of creating his own VM he could only get the default settings none of the upgrades…

Any assistance in this regards is appreciated.

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