Property locked for updates

Summary:

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I have a property assigned to a dimension called account type on a dimension (Account) which I cannot amend for any account dimension member.

There are no validation rules specified on the dimension itself (account dimension) that is preventing me from amending this property. I cannot see where this restriction is set on the property. Is there a way of checking and disabling the validation to allow the property value to be amended for a selection of members and then re-enabling the validation?

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