Drips coffee from the coffee tank (by 4 users)

after taking one or two cups of coffee the tank drips after a while.i have cleaned around and under the despensing mechanism ring and it still leaks.
i replaced the tank abouta year ago and its happening again. this obviously is a design defect problem. is there any way to prevent this leaking? or do i just go back to the caraffe coffee machine and throw this brewstation away.