Many Muslims have the misconception that heaven and Jannah can be used interchangeably. While they do mean the same thing in regards to the english language they are referring to separate things when mentioned in the Quran.
Jannah when translated from Arabic means Gardens. The highest ‘ceiling’ of these gardens is known as Al Firdaws, which can be translated into Paradise.
The heavens are refering to whatever is above us (the skies). We know from the Quran and Sunnah that there are 7 heavens (7 ‘skies’). These are not related to Jannah/Paradise/Jannah.