plugin crashes site when activated

We updated our theme, UDesign, and had to increase the php to 7.1. Now, when we reactivated all the plugins, the All-in-one Calendar plugin causes the site to crash. I have the most current update of the plugin installed. Currently the calendar plugin is inactive and the site is up.

Interestingly enough, when I deactivated all the plugins and reactivated All-in-one Calendar plugin first, it did not crash the site. It may be an incompatibility issue with other plugins. I have no idea, but this plugin seems to be part of the issue from all the trouble shooting I’ve done.

I am not a tech guy, so please respond so I can understand.

Thanks so much!!!

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