MDEK1001 Accuracy and debugging

Hi;

I am working on a project where I have an autonomous vehicle working outdoors using GPS and IMU. The issues that I have now is that I have MDEK1001 modules and I currently they have 10-20 CM accuracy and the data is missed and I do not know the reason. I was wondering how can I improve the accuracy and reliability?
Is there anyone for help?

Thanks :blush: