LTE -NB connection issues

[sandris]

Do anyone had success with keeping a stable NB-IoT attachment through a sleep cycle.
I have previously succsessfully connected to the Telenor NB-IoT network, but are not able to do so suddenly. Further on I'm trying to understand how to get a stable connection after a deep sleep, using the py.go_to_sleep(False) command with the pytrack.

As far as I understand this command should keep the attachment to the network through a deep sleep cycle. The attachment is kept sometimes but not often enough to be able to use. Updated to newest firmware.

NB-IoT Firmware: (lte.send_at_cmd('ATI1') )
UE6.0.0.0
LR6.0.0.0-38729

Minimum example code:

from network import LTE
import time
import machine

lte = LTE()
lte.init()
#lte.reset()

lte.attach(band=20, apn="mda.ee")
i = 0
while not (lte.isattached() or i > 15):
    time.sleep(1)
    i=i+1
    print("", i, " seconds passed")
if i > 15:
    lte.reset()
    machine.reset()
lte.connect()       # start a data session and obtain an IP address

while not lte.isconnected():
    time.sleep(1)
print("Connected")