Prexisting or Preexisting: How To spell?
The word Prexisting is misspelled against Preexisting, which is present continuous of "Preexist"
Preexisting has double "ee" is mispronounced as "e"Remember double 'EE' in between the strings Pr & xisting which should not be misspelled with single 'E'
Wrong Spelling:  Pr-e-xisting  Correct Spelling:  Pr-ee-xisting 
Find more wrongly spelled words of Preexisting to spell it well.