TE506501en Coffee does not taste good after descaling

Tach zusamen
We bought the above fully automatic coffee machines in September and are also satisfied so far.
Only after the first descaling the first 3 coffees did not taste good. My feeling tells me that the rinse after the decalcification process is too short.
When the process "Decalcifying" appears the function "Clean tank / Fill start press. The water tank is filled to max with fresh water. Then the last item in the program runs "Descaling running". According to the instructions, this program item should last about 3 minutes. With our device this process only takes about 1 minute and only about 200 ml of water is taken out for rinsing.
I have also already written an e-mail to Siemens,the machine said to the workshop,then I called again in the workshop and the employee says that is not ok, the water container must be empty after rinsing.
As a machine in the workshop.
Now the machine came back after one week, allegedly no error is detectable.
test run without disinfectant, error is still there.

My question to you is now, how is your machine the tank empty after the flushing process or are only about 200ml out.

>I hope for your help

Volker

I've also noticed that the machine doesn't flush for three minutes.
But I did some manual rinsing myself afterwards. I'm sure the machines will be fine. I couldn't find any bad taste.

So
The machine is really fine.the coffee tastes good after 2 decalcifications.
However, it is very important to clean the water tank thoroughly and rinse it several times before rinsing.

Greet Volker