What does the cryptic crossword clue "Miserable type knew tablet to be faulty (3,7)" mean?

The wordplay uses an anagram. anagram of KNEW + TABLET = WETBLANKET The answer is WETBLANKET.

Miserable type knew tablet to be faulty (3,7)

Daily Mail Cryptic #17137 | 11 Across | 2023-07-10 flower