Hello @vivienkiong56 ,

I noticed other posts that show and discuss many aspects of the email configurations.  Your error above seems related to incoming emails. When you temporarily disable the incoming email configurations, does the error go away?

You have likely already seen other posts in this community related to email issues. These links below may be useful for screenshots & discussions of configurations using Gmail .  In case you have not noticed previous posts, here are some convenient links:

I hope these posts lead you to an answer.