Mispent or Misspent: How To spell?
The word Mispent is misspelled against Misspent, which is past tense of "Misspend"
Misspent has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings mi & pent which should not be misspelled with single 'S'
Wrong Spelling:  mi-s-pent  Correct Spelling:  mi-ss-pent 
Find more wrongly spelled words of Misspent to spell it well.