zigbee mesh - ESP32 H2

Hi
I am trying to create zigbee mesh through multiple esp32 h2, but i still cant configure the router to extend the network connection range… i have already use sample from esp-idf-zigbee but i loose frequently some esp32h2 in my zigbee network although they are place in chain 4-5m one from an other… what did i do wrong ? Can any help me