No custom templates have been used, I also did a search via command line and there are no custom templates.Did you have any custom FXS templates on your system before the upgrade? (we have to be sure just in case)
If any entries were created which are now invalidated after upgrading and removing the custom templates, it could cause this issue.
Could you also please tell us some more details, like how exactly did you perform your upgrade on this system?
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