Some routers have two separate Wi-Fi networks (one for the 2.4 GHz band and another for the 5 GHz band), which require you to manually connect to the band you want. 

Sometimes it's tricky to connect your RoboVac to your mesh network, as they use a single WiFi SSID for 2.4 and 5 GHz radio frequency and you can't designate which band you're using.
 

eufy Clean App only connects to the 2.4 GHz band, so you'll need to connect to the 2.4G band on your mesh wifi network.  

If normal troubleshooting fails, you can try taking your RoboVac and moving far away from your mesh nodes.  Get as far away as you can while still maintaining a connection to your wifi.   The 2.4 GHz band travels much further than the 5 GHz band - so there's a greater chance you are now connected to the 2.4Ghz band.