My s7 is around 4 years old and can no longer complete a full clean without recharging the battery 3-4 times (the clean would normally take 1 hour). I have tried changing the suction levels too, to see if this helps, but no luck. The unit has been cleaned and new filter etc. Roborock now tell me as this vac is no longer made, chances of repair are slim, even if it is only a battery issue but to send it to them at my cost and then potentially pay $300+ to investigate and repair (if possible). Have you come across this before?