Ring doorbell pro 2 sometimes no Ring alert but only motion recorderd

I replaced my Ring doorbell pro with Ring doorbell pro 2. With the pro I didn't have any problems. With the pro 2 I miss sometimes the Ring alert. In that case, when someone is at the frontdoor and pushes the Ring button the Ring Chime doesn't give a sound and don't get a message on my phone. The only sound is at the Ring at the frontdoor. In the history there is a recording of the motion but no Ring alert. So I can see the person walking up the frontdoor en pushing the Ring button. The WiFi router is near the frontdoor and has a very strong signal. The device gets enough electricity. I contacted the Ring helpdesk and they helped me check the settings. I have tried al lot of different settings but the problem still excists. Did anyone else experience the same problems and what is the solution?