ok i have a 4wd robot building base as seen on my account's picture i connected right side motors with together and left side motors with together then iconnected them to h-bridge they worked then i needed to take it appart for some reason when i recconnected them only right side was working why is this how can i fix this

this is how i installed h-bridge int,1 to ez-b d15 h-bridge int 2 to ez-b d16 h-bridge int 3 to ez-b d17 h-bridge int 4 to ez-b d18

thnx