Hi! My issue is that the Zapier is erroring some of the time. On errored Zap Tasks, in Step 2 in Data Out is showing as “A confirmation email was sent to XXXXX@gmail.com since a double opt-in list was selected for this Zap step. Learn more at https://help.klaviyo.com/hc/en-us/articles/115005251108-Overview-of-the-Double-Opt-In-Process”.
However, they are set to go to my Klaviyo list UfPmis, which is setup in Klaviyo to be single opt-in.
Hey there
I did some checking and it seems that you’re running into a bug with the Klaviyo app on Zapier. I’ve added you to the list users that are being impacted by this same issue.
There aren’t any known workarounds reported for this at present unfortunately. And we don’t have an ETA on a fix, but you’re on the notification list so we’ll definitely send you an email notification the moment it is resolved. Sorry to not have an immediate solution to share here. If we come across any workaround in the meantime we’ll be sure to share them with you here! 
Hi. Can I also be added to the notification list when this bug is fixed? Thanks.
Hi
I have added you as another affected member to the open bug report. While we don’t have an ETA for the bug’s fix. We will keep you in the loop via email once there is.
Thank you for your understanding.
Hi there - this is an issue for me as well.
Hi
I have added you as another affected member to the open bug report. We will let you know via email as soon as there’s a fix for this.
Thank you for your patience and understanding.
Please add me as well - same issue here.
Hi
I have added you as another affected member to the bug report. We will keep you in the loop via email once there’s a fix available.
I appreciate your understanding.
I’m having the same issue. Can you add me to the notification list?
I’m so sorry to hear that
I have added you to the open bug report. While we can’t provide an exact timeframe for the bug’s fix. However, we will keep you in the loop via email once it is fixed.
Thank you for your patience and understanding.
Please add our account as well.
Thank you!
Hi there
I have added you as another affected member of the bug. We will keep you in the loop via email once the bug has been fixed.
I appreciate your patience and understanding.
Hi folks,
Good news - a fix for that issue with the double opt-in setting was shipped recently! 
I expect you will have already read the email notification that was sent out, but in case you missed it here’s what you need to know:
“We worked with the team at Klaviyo and determined that updating the Zapier integration to the latest version of their API should help to address this problem, so we have done so for the entire integration. In the case of the Add Subscriber action, you'll know if you're still using the older version of the action if it says "Legacy" in its name. So, if you are still having problems with confirmation emails going out incorrectly, please try switching over the the newer Add Subscriber action instead.
Unfortunately, due to the changes between the previous version and newest version of the Klaviyo API, we were not able to move these over automatically. The older "Legacy" versions will still work as they did before, but the newer version of the action should address this bug.”
If you have any questions or run into any issues in switching to the newer version of the Klaviyo app let us know!
I built my zap only a month ago and still have this issue.
I used Zapier to link new entries in an Airtable base to Klaviyo. The goal is to auto-subscribe these contacts to our newsletter list in Klaviyo.
In our newsletter list, ‘Single Opt-in’ has been selected for ages, yet our customers receive an email to confirm their subscription to the newsletter.
I have no clue how to stop these confirmations from popping up.
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