Why my wireless cameras have a long delay of notification since I upgrade to eero before was 5 seconds delay!now more then a minute.

This is the right modem ? RCN swapped from a bigger modem to this small one ! I’m only getting 745 mbps out of 1 TBPS and I’m getting 2 bars on my cell phone on connection and I’m next to the beacon,do I need to get another beacon?