The most common and most likely answer to this crossword clue is the 8 letter word MISTAKEN
I've seen this crossword clue in The Guardian
M
I
S
T
A
K
E
N
More clues leading to the result MISTAKEN
- Investment minister has secured in error
- Wrong girl abducted according to reports
- Wrong name makes it invalid
- Notes written down are wrong
- Wrong lass almost clutched
- Taking post in government dept could be misguided
- Faulty judgement practically accepting bet
- Male elected to keep investment, in error
- Why James Bond can’t marry his boss in error
- Sounds like girl’s kidnapped in error
Buddy explains!

The straight part
We know that "Wrong" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wrong = mistaken.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 MISTAKEN mean?
MISTAKEN verb- To understand wrongly, taking one thing or person for another.
- To misunderstand (someone).
- To commit an unintentional error; to do or think something wrong.
- To take or choose wrongly.
- Erroneous.
- (with a copula verb, often with about) Having an incorrect belief.