This indicates an issue with the defrost drain tube.
If this tube is blocked or if it freezes the water will drip/leak.
Please try this:
Leave it unplugged and empty with door open for around 12-24 hours.
Then plug it back and wait for another 4-8 hours.
The problem should be resolved.
However, if the issue appears again you will have to unplug it and then remove the rear off the appliance.
The tube is located under the evaporator on the drain pan in the compartment next to the compressor.
Thaw the drain tube, you may use hair dryer or pour warm water in the tube, and ensure it is not clogged/blocked.
Also, clean the drain pan to resolve the issue.
However, if the issue appears again then the problem is with defrost operation.
You will have to test/replace the temperature sensor and/or defrost heater element to resolve the issue.
Alternatively, you may call Hotpoint at 03448 225 225 to book repair.
If there is anything else I can help you with, please let me know.