RUTX11: apn setting is not persistent

We use a script to provision RUTX11 router where we set over 40 different settings, then verify them. Only one (network.mob1s1a1.apn) does not consistently get saved. Sometimes it does, but not always.
Our firmware is 7.0.5.4 and the sequence of commands is:
uci set network.mob1s1a1.auto_apn=0
uci set network.mob1s1a1.apn=‘apn-name’
uci commit network
/etc/init.d/network reload

Any reason