Problem setup cam battery

On 19 march 2020 i have received a new ring spotlight cam for the front yard. The old device didnt work well so i get for free a new one.I have two devices, 1 for the front yard and 1 for the back yard. For both devices i get the protect plus plan since 09-2019. Since i installed the new front device i mentioned that the front device did not linked to my protect plus plan. The back yard device is still recording well but my front device unfortunately not. Both devices are registered at the same location. Previous week i contacted you guys and the advice was to re-install the ring app and the device again. The problem now is that the device can not make a connection with the ring app. During the setup the light of the device is blinking red and then it loses the connection. I have no problems with the other device, thats working normal.