Is it permissible to continue working with a company after voluntary retirement from social security, and to stop paying social security contributions, while receiving half of the retirement salary?

The ruling on social security funds varies depending on their system. It is permissible if their system is cooperative and adheres to Islamic regulations, and forbidden if it is non-cooperative or does not adhere to them. If permissible, it is allowed to take the entitlements; otherwise, it is not permissible to take anything beyond what was deducted from the salary.