An advisor is setting up a Household in Financial Services Cloud for their new clients, Oliver and Macie Dogging ton. The advisor created a Person Account record for both Oliver and Macie, and a Household record for the Dogging ton household. While creating the Household group, the advisor attempted to input the below information but received an error.
Member Name: Oliver Dogging ton
Role in Group: Client
Primary Member: Enabled
Primary Group: Enabled
Activities and Objects to Roll Up: All
Member Name: Macie Dogging ton
Role in Group: Spouse
Primary Member: Enabled
Primary Group: Enabled
Activities and Objects to Roll Up: All
Based on the information provided, what caused the error that the advisor received?