2: BadValue

What does it mean?

An invalid or unexpected value was passed to a command or query. MongoDB could not interpret the argument as an acceptable value.

Why does it happen?

An invalid operator argument, an out-of-range number, an unsupported option value, a malformed sort specification, a malformed query expression, or an inappropriate combination of parameters.

How to fix it

Correct the argument based on the field/value hint in the error message. Validate command and query options against the documentation. Check the format of sort/projection/aggregate expressions. Bring value ranges and types into the valid range.