ParseException line 12:84 mismatched input 'student' expecting StringLiteral near '=' in specifying key/value property

This error message suggests that there is a syntax error in the code at line 12, column 84. The parser was expecting a string literal after the equals sign, but instead found the word 'student'.

To fix this error, you should check the code at that line and make sure that you are providing a valid string literal as a value for a key/value property. It's possible that you may have accidentally left out some quotation marks or used the wrong syntax for specifying a string value.