New Bosch dishwasher drain pump runs continuouosly

Model Number: SMS65E38GB
Brand: Bosch
Age: Brand new!

Hello,
Our new Bosch dishwasher was installed 3 days ago by currys. This is our first dishwasher and we haven’t used it yet. I had a question regarding a particular behaviour and am hoping the experienced people on this forum can help.

Even when the appliance is switched off i can hear the sound of water running inside. When I open it i cannot see any water flowing but just a few water droplets , which i guess was left over when the installer tested it. So I open the filter fitted at the bottom and in the hole below I can see water flowing across. I guess this is the waste water drain pump. Water flows for 50 seconds precisely and then stops for around 35 secs. this cycle repeats continuously. I figured out that the water wasn’t coming from the water mains connection and wasn’t flowing into the drain outlet as this behaviour continued even when i disconnected both. It only stops when i switch off the power supply. Has any one experienced this?

Calls to currys and then to bosch haven’t helped as the help desk assistants said they are not technical and will have an engineer visit my home next week. They will charge me a hefty sum ( 20{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} of the cost of the appliance ! ) if there is no fault, so I want to make sure this is a fault

Thanks for listening!

Sameer