Error message when sending customer statements {send success toast} {send warm toast} does anyone know what this means

Hello Dougiebennett, thanks for posting on the Community page,  Can you try clearing your cache and cookies, to all time, close the browser down, reload it and see if it resolves it or if you still have problems. 

Hi Ashleigh

I've just tried that but it hasn't made any difference

Hi dougiebennett, thanks for trying that. 

We're aware of an issue with this error message and our team are tracking this on our investigation with reference INV-87296. Please note, this warning does not affect the sending of the statement and these will still send to your customer as expected. If you'd like to receive updates on this investigation, please begin a chat so that we can take some account-specific information. :)