Error - cannot change contract attributes because contract type is currently in use

When editing a contract type, you may encounter the following error - Cannot change contract attributes because contract type is currently in use.

Once a contract type is applied to a contract line item, you can no longer edit the type. To make edits you'll need to first remove that contract type from all existing contract line items. To identify these, go to Topics | Contract Line Items. Search by contract type. Edit each type and change to a different set of terms.