Duling or Dulling: How To spell?

The word Duling is misspelled against Dulling, which is present continuous of "Dull"

Dulling has double "ll" is mispronounced as "l"
Remember double 'LL' in between the strings du & ing which should not be misspelled with single 'L'
Wrong Spelling:  du-l-ing 
Correct Spelling:  du-ll-ing 
Check more misspelled words of Dulling to spell it correct.