Deposits will remain in the Client Account until they are transferred to the Deposit Account or into the TDS Custodial Scheme.
Once you have received your TDS ID from the TDS enter it as follows, go to the Tenant, click Tenancies, double-click to Edit the Tenancy and insert the Deposit Scheme ID.
If you do not operate a Deposit Account, Deposits will remain in the Client Account. When adding Tenancies set the Deposit Held By option to Client. Read more about the different deposit types here.