Nordic ble is unable to send data to the host computer

[Lappland]

Sending array unit8 type data using BLE failed, and attempting to take 2 bytes of data from the array and send it also failed. Does anyone know what this log error means? How to solve it?

[Jakob Ruhe]

Error 22 typically means "Invalid argument". 

Perhaps share the code you are using and which board you are running on so that others can reproduce and fix the problem you are facing.

[Vidar Berg]

bt_nus_send() will return -EINVAL (-22) if the client (host) is not subscribed to notifications from this characteristic.