Could be calc deposit buildup from water had the same problem a while back buildup was inside the tubes and turned almost into rock inside it if thats the case junk it and buy another coffee pot just my sugestion if not you can try C.L.R ( calc lime and rust remover) but make sure you rune water through the pot several times before you use it again after you use clr.
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Could be calc deposit buildup from water had the same problem a while back buildup was inside the tubes and turned almost into rock inside it if thats the case junk it and buy another coffee pot just my sugestion if not you can try C.L.R ( calc lime and rust remover) but make sure you rune water through the pot several times before you use it again after you use clr.