Flatening or Flattening: How To spell?

The word Flatening is misspelled against Flattening, which is present continuous of "Flatten"

Flattening has double "tt" is mispronounced as "t"
Remember double 'TT' in between the strings fla & ening which should not be misspelled with single 'T'
Wrong Spelling: fla-t-ening
Correct Spelling: fla-tt-ening
Find more wrongly spelled words of Flattening to spell it well.