shows the device in lsusb. It also is shown with the first line of the output from dmesg.
This means the system sees it, but is not properly configuring it.
I found this link with a search for the line I quoted above and it seem relevant to your issue. I realize that is an old bug discussion but it likely will still apply in that it seems the fix was to create a udev rule so the system properly recognized and configured it. There were other links as well but I did not review all.
If that modem worked with F34 and the upgrade to F35 broke it then it certainly should be reported as a bug since something caused the previously functional device to be no longer configured properly. In fact I would venture that it is almost mandatory that a new bug be filed, even if you get it working with a udev rule. Only with a bug report will the developers be informed of the regression caused here.
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