Problem Statement/Rationale

Explain plan shows no index applied for query, while interpreting it shows index was used

Please be sure to attach relevant logs with any sensitive data redacted.

Steps to Reproduce

Create aggregation for match, group and project stages, 
in match two parameters were added for filtering.
 while running aggregation explain plan it shows no index was used, while when interpreting query
with mongo DB assistant it shows index was used.

Expected Results

Result was same, but since mongo explain plan shows index was not getting used.
we added addition stage of sort before group as found through researching
which made our query slow, hence post discovering index were used but mongo compass was misleading with message we removed.

Actual Results

Same result.

Additional Notes

None