You either have a slow draining drain, or a blocked drain. This can be caused by sediment, oils and hair which over time, clog the drain until they restrict the flow of water. You can try some home remidies first, but depending on the severity of the problem, you may still have to call the rota router man to unblock it all, using compressed air which blasts it open.
You can buy a plunger which creates a vacumm around the pipe and forces the water to move. Alternatively you can buy a drain unblocker in a can, from the hardware shop or supermarket. This often contains harsh chemicals like acids, which discover the build up and dispell it into the system, and is not very good if you are on a septic tank system. It is not the most environmentally friendly option.
If this does not work, boiling water poured into the plug hole, can discover fats, but be careful of plastic pipes that can melt, causing a bigger problem.
You may have to get a plumber.
You can buy a plunger which creates a vacumm around the pipe and forces the water to move. Alternatively you can buy a drain unblocker in a can, from the hardware shop or supermarket. This often contains harsh chemicals like acids, which discover the build up and dispell it into the system, and is not very good if you are on a septic tank system. It is not the most environmentally friendly option.
If this does not work, boiling water poured into the plug hole, can discover fats, but be careful of plastic pipes that can melt, causing a bigger problem.
You may have to get a plumber.