Hi, Benny.
Please do these, in order:
- Could you follow the steps here and then install any updates you see? Also, please check the “Additional Drivers” tab on the Updater Settings (as shown on pics on that link).
- Please also check if there are any broken packages in Synaptic. Right click on any broken package and “Fix” it.
- If these steps still don’t fix it, please Search ‘broadcom’ (without quotes) in Synaptic. I see at least 4 different driver packages (three of them are broadcom-sta) but I don’t know which one would be appropriate for your adapter. You could try them one by one. Again, only install these if the first two steps don’t fix the issue.