2008 mercedes ml550 gas fumes after fill up no overflow.

What is your question?

Had gas pump assembly and lock key replaced by mechanic per advised cause of strong gas fumes.

What makes this problem better or worse?

Worse when ac on and/or after fill up no overflow. Better when only 1/2 tank.

How long has your 2008 Mercedes-Benz ML550 had this problem?

Few months off and on