Cannot read field "scale" because "val" is null

Summary:

When doing bulk update to edit schedule, the system gives an error - Cannot read field "scale" because "val" is null.

This is by far the worst reasoning for any error.

What does this message mean ? & how to resolve ?

The workaround that we have done is to edit schedule for each resource individually and it works - but you cannot do this all the time.

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26C

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