Client non comunica con il server quando cayenne non è connesso

my esp8266 clients are connected to servers via a router. when cayenne and connected everything is fine to and from cayenne and to and from the server. But when I do not want to connect cayenne, the client will no longer communicate with the server even if in the network they are connected and their ip has not changed. Have any such problems been reported?
I’m going crazy because I do not understand if it’s my problem or incompatibility with the used libraries that are these:
ESP8266WiFi.h, ESP8266Ping.h, WiFiClient.h, WiFiManager.h, EEPROM.h, Timezone.h, NTPClient.h, CayenneMQTTESP8266.h.
The tcp port used and the 8080 this command: WiFiServer server (8080);
Thanks in advance