Lock Inclusions After Start: Is the equivalent of telling the campaign to be a one-time campaign. It will take the initial audience and never let any new records in. It will also ONLY check the audience at the beginning of the campaign and not when subsequent tracks run.
Use this setting with care. If you are running an adhoc (one-time) campaign, set an end-date rather than using this setting.
"Lock Inclusions After Start" should never be used in automated campaigns where new audiences are desired, rather than sending marketing communication to the same locked audience.
Please work with G2D support if you think this setting is needed.