Modem Manager strange issue


I have a very strange issue with modem manager. I have 4 Quectel EC25 modems configured with modem manager as protocol. 3 of them when they are connected they use wwanX interface correctly while one which has the same config with other 3 sometimes uses wwanX and after sometime it changes and uses pppX interface.

The config looks correct and for device in the config I am using the full path as it is recommended. However, in Luci I see the following.

Any help of how to tshoot the issue will be highly appreciated.