Error while updating Hosting Plan in HC

Question: Whenever I try to update my existing plans from Hosting Plans :: My Plans :: Edit Plan. I get the following error: Error: 70100510: Update failed; some Resources are in use. Why?

Solution:
In HC, resource(s) of a plan cannot be edited/added if that plan's instance is sold and there is an excess usage of any one of the resource in the plan. For example if Bandwidth is consumed more than allocated for the sold plan then HC will not allow to edit that plan at any cost. Before editing that plan you will have to sell addon for that resource to that webadmin.

Here is the step by step procedure for resolving issue for updating any plan resources:

How to replicate the issue:

    1. Login as "Reseller" in HC panel.

    2. Go to the location Hosting Plans :: My Plans :: Edit Plan.

    3. Try to edit the Plan. Here you will get error Error: 70100510: Update failed; some Resources are in use.

    4. Click on Show/Hide Report Link at this stage which will reveal the cause of this error.

    5. In this location, problem User (webadmin) and the resource which he/she has used more than the allocated amount would also be shown. To confirm this violation of consumed resources, it can also be checked from
Hosting Quota Report of this user Reports :: Hosting Quota :: Quota Report.

How to resolve this issue?
 Follow these steps:

    1. Login as "Reseller" in HC panel.

    2. Go to the location Hosting Plans :: Add-Ons :: Sell Add-On.

    3. Here sell Add on of resource whose quantity is violated by the particular webadmin(s).

This will resolve the issue and now HC will allow you to edit OR add new resources to the plan easily from Hosting Plans :: My Plans :: Edit Plan.