How to reactivate concept and application

My grp 1 syllabus was done roughly around November 2025 and I have to give both grp in dec 26

Now I have forgotten the application of grp 1 subject like concept are there but in faded way I can recall them but application is absent like I am unable to solve questions and recollect the concept while solving the question

In short getting fully blank while solving the question

Any solution?