polygons merge in one shapefile

Hi , i have a shape file with it made of several polygons which are connected to one another the polygons over lap one another with lines. See attached diagram

what i would like to have is one polygon , which is defined by the perimeter of the shape. So i would like there to be no lines in the middle of a shape just the permiter line

i have tried using the merge and dissove funcations , but i m still left with some lines on my shape

Does anyone have some ideas ?

Thanks a lot Jack Attachment 32762Attachment 32762Attachment 32763

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