make sure that you dump code of gatt_client in client and gatt_server in server. And make sure that if the esp32 is new do not directly plug it in without loading server code into it....cause we dont know which code is currently running in the new esp32 which we are using as server...that might give...

can you tell me how?

can you explain how because im using esp32 wroom and my at+blecfgmtu is set to 23 and when i try to set the data len to something else it throughs and error..

after > don't include \r\n with your data..

you said your own code what does that means ?? im trying to send at-commands using usb-uart to esp32 at 2000000 but unable to communicate..