ESP32S3 : BLUEDROID : Why characteristic write is 20 chars by default ?

[ThomasESP32]

Good morning,

I am working on Esp32S3 using the Bluedroid BLE stack.
I defined my characteristics with size 255 bytes long and I use a BLE Terminal on a tablet
in order to write things on the characteristics.

The BLE Terminal does not have to functionnality to negociate MTU.
It seems that I do not have the possibility to write more than 20 chars at a time by default do you know why ?
I which I could change this value in order to send long commands to my application but I don't know how to do
it.

Best regards,
Thank you for your help,

Thomas TRUILHE