Plastics fitment ?

Just got the grizz home last night . I noticed the battery compartment cover does not like to stay tight to what used to be the gas tank. There is a molded groove in the body panel that holds it tight to what used to be the gas tank. I can press down on the cover and set it in place ,ride a little bit and it pops loose , obviosly it doesn,t hurt any thing just wondering if this common ?