We also removed any call to the incorrect function. I can’t find a reference to it here or anywhere else in the 2.12.10 code: https://plugins.svn.projectdmc.org/paid-memberships-pro/tags/2.12.10/shortcodes/pmpro_member.php
I wonder if something didn’t go well in your upgrade. You can try to patch your own copy of your site by copy/pasting that file above.
You can also try to safely remove PMPro and reinstall it from the latest version and see how it works. You can remove the directory manually via FTP or you can remove the plugin from the plugins page, but FIRST go to Memberships > Settings > Advanced Settings in your dashboard, scroll to the bottom, and ensure that the “Uninstall PMPro on deletion?” option is set to No and saved.
We don’t like folks to have to do that, which is why we pushed a 2.12.10 version with that small change. The version bump should allow you to update automatically.
Sorry again for the trouble the update caused. If you find some other information about the issue, let us know.
My mistake, I was still running 2.12.9