Blanco BDSD-st soap dispenser problem

I can't refill it. I can remove the plunger but I can't get the guts below off for refilling. When I looked behind the sink, I note that the bottle
reservoir is miss-shapen because of suction. There's some soap in the bottle. Because it is behind the sink I can't really work on it. Is there anything I can do to release the suction from top of the dispenser? Anything else besides calling a plumber?
Art Hoffman
Boynton Beach, FL
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