Question about E4 - 387045

I ordered the Roborock E4 but it won't connect to the Wi-Fi. No matter what I try, including renaming the Wi-Fi, it won't connect to the app. The description in the manual is also rather poor. But the app should actually work and guide me through the process. For me, however, it stops at the first step. I have put the Roborock into pairing mode, now it would be nice if it would also connect. Has anyone had a similar problem and solved this already? Thank you very much.