Plugin does not work after updating plugin.

Hi. My name is BSC.

Plugin does not work after updating plugin.
I sent out a test email after completing the settings as before, but I get an error.
I’ve done a lot of searching, but I didn’t see much of an error like myself.

I will attach a video about the error.
https://streamable.com/fj520

If you don’t mind, please check this error and give me a solution.
Thank you in advance.

Best Regards,
BSC

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