If you cannot connect or re-connect your Bing source, try the following:
Ensure that multi-factor authentication has been enabled for your Microsoft account.
Connect a new source or reconnect an existing source in Funnel.
Create a new set of credentials. You should be prompted to enter an email address. If you're not prompted (i.e. the sign-in process starts automatically) then sign out of www.bing.com or use your browser in Private/Incognito mode, and try again.
If Microsoft states that your account exist both as a "Work or school account" and a "Personal account", select the option that was used when you got access to Bing Ads. If you don't know which one to use, pick "Personal account" and if that doesn't work, try "Work account".
Please note that a Microsoft email adress could actually be 'connected' as both personal and work account in Microsoft.
How do I remove my credentials before creating a new set?
To be able to remove a set of credentials you will need to remove the bing sources that are using them.
Campaigns and/or metrics are missing
Restrictions with the Goals report
The Goals report does not support certain campaign types, such as “Shopping”, “Dynamic Search”, or “Audience”. Furthermore, the Goals are only attributed to conversion metrics (as seen in What data can I get from Bing), not to other fields e.g. Spend, Clicks and Impressions.