Extension of employment
If your employment is extended and you have obtained a work permit to work in Sweden, you need to apply for an extension of the permit.
In case your current employment is extended, you can carry out the application as done earlier. However, if the extension concerns a new position, the employer is requried to advertise the position and you will need to apply. Bear in mind that during the processing period of your application, there may be restrictions on the possibility of leaving the country. Contact the Swedish Migration Agency (Migrationsverket) for details on your specific case.
More information can be found on the website of Swedish Migration Agency: Extending a work permit