Oh I see, fluctuating score in modules. I think you're probably too anxious about your exam. Work on your basics in both reading/writing. Forget about the failed attempts and rather introspect about what you could've done better.
I would also suggest, taking a gap between the re-attempts to increase your skill level, lower anxiety and help you get minimum 6 overall.
I'm sure you would be able to achieve a minimum of 6 in each module.
This way you can easily apply under SDS.