Join manual mode and link check issue

Hi all,
I’ve setup the xdot as manual join with NJM=0. Also link check is active with LCC=2 and LCT=2.
NJS replies always 1.
After a send operation there was a message “No response from network link check” and NJS changed to 0.
If I try to send again, I cannot because of “network not joined” error.

How can I revert this situation because I cannot send again? Will link check do this?

MultiTech xDot
Firmware: 2.0.14-(detached from 3699e9b)
Library : 2.0.14-(detached from 7f6b74e)

Thanks!