Beautiful blender, food flooded (Monday Model?)

The mixer looks good and also makes a good impression processed. The state is also good. However, the lid is very firm and can only be removed with "violence". Unfortunately I can not say much more to the mixer because the following problem has occurred: From the first operation (factory state) has the detachable knife solved when mixing and flooded the kitchen with just 2 liters of water. Very ugly, as some cookbooks were softened and the water has run into the base cupboards. So dismantled everything looked again in the manual, everything reassembled. The seat of the knife was particularly monitored: engaged and seated, as it should. So second attempt: Smoothie. Mixed a few seconds ... the kitchen flooded with smoothie. That's it then! Have specially bought an expensive device, so this does not happen. Because it apparently only concerns me perhaps a Monday model. But I risk no more flooding in the kitchen and send the mixer back directly. Pity about the device and the wasted time during kitchen clean ...