It could be that the 2FA provider no longer supports the endpoint used to generate the image. Unfortunately I have no plans to update any vBulletin product at this time.
Could you please give me the details of someone who may be able to help me fix this problem, like the developer or the name of the 2FA provider?
Thank you
Looks like Google has taken the API offline, you can try reaching out to them and asking them to re-activate the https://chart.googleapis.com/chart API URL.
We hope your ticket regarding Two-Factor Authentication has been addressed to your satisfaction. This ticket has now been scheduled to be closed.
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