When your account becomes insolvent, liquidators would come and initiate liquidation process.
If the liquidator uses traditional DeFi approach, your full position would be taken over so you will lose all of your position and margin token.
If the liquidator uses Auto Liquidator approach, your position will be partially liquidated to a safe state that meets the initial margin requirement.
For details of the different liquidation approaches, check out How do I become a liquidator? for details.