Your work or research situation must be unchanged.
You must meet the same requirements as when you applied for the first time.
Requirements of the type of residence permit you have
Your residence permit must be renewable. If you already have held the residence permit for the maximum amount of months or years, you cannot apply for renewal.
Residence permit for:
Is the permit renewable?
Trainees
No
Researcher with own funds
Yes
Requirements of persons who have changed employers or research institution