Did it say say that there were no more bridges left?
Every new one you go under it counts down, in the bottom left of the map there are a bunch of bridges in a little canal sort of thing, there are two bridges there that may get missed, one is really low to the water (hard to go under) the other is like a curved bridge with a large pillar you have to go through the left of it, just go under it on both sides of the pillar just incase.
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^sticktoon, epic^ |