Hi Abhi077,
That is an interesting 'technical' issue, since April, 2018 is when the GMAT went through its most recent format change (to the current, shorter version). Since you are referencing an older Exam Score (in the older, longer format) - which you cancelled - maybe the default settings in each user's Official Account at
www.mba.com are such that they won't list older, cancelled results (since it's unlikely that someone would choose to reinstate a result that at this point is over 3 years old). That having been said, it almost certainly DOES count towards your 8 lifetime-Test-limit.
Are you interested in re-instating that older Score?
GMAT assassins aren't born, they're made,
Rich