The most common and most likely answer to this crossword clue is the 7 letter word UNLEARN
I've seen this crossword clue in The Guardian
U
N
L
E
A
R
N
More clues leading to the result UNLEARN
- Try to forget about leaving vague information at the end
- Try to forget information nun spread about king
- Forget studies of tragic role in curtailed Nunn production
- Rid one’s mind of tragic figure stopping sister cycling
- Forget a French student with merit
- University close to Pakistan’s south gets student to forget lessons
- . Forget king in news, union leader is the heading
- Forget naughty nun is entertaining king
Buddy explains!

The straight part
We know that "Try to forget information" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case try to forget information = unlearn.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does UNLEARN mean?
UNLEARN verb- To discard the knowledge of.
- To break a habit.