This is very strange indeed! Do you have a screenshot of an old newsletter that shows what the bottom should look like? I looked at the latest newsletter in your account but I'm not sure if what should be at the bottom is there or not. Do you mean that a separate block is completely disappearing?
One thing I do notice is you are still using our second-generation editor, also known as the legacy editor. If your process is to make a copy of an old newsletter over and over again, it can cause some funky things to happen after a while. I can't say for sure this is the cause, but I'd be curious if you started a fresh template, or went back to an earlier campaign and copied from that, if the issue would persist.
I encourage you, if you haven't already, to give our Third Generation Editor a try. It's built from the ground up to be mobile responsive and is really easy to use! I can update your account for free if you'd like and it won't erase any of your previous work! Though previous campaigns will remain in the legacy editor, even when you copy them.
EDIT: I did a little digging and saw that you engaged with our chat team and provided a couple of screenshots, so I can definitely see that a block is supposed to be there. I also saw they tried some troubleshooting with you that didn't work.
I was able to replicate your issue so I went back to an earlier newsletter (the December email) and copied that. I did not experience the same issue. My suggestion is as above, to either start with a fresh template or copy from an earlier newsletter. Please let me know if this works for you!
Nick S. Social Media & Content Manager
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