Adobe Sign emails are not being received

Hi, 

I have sent paperwork to one of our cohorts for them to sign but none of the learners recieved emails from Adobe, they have checked in their Junk and their Spam folders but they weren't in there. 

They all work for the same company and have the same domain name, we do however have learners from the same company who have recieved these. 

I have spoken to their IT department and they have said the following. 

Adobesign isn't seeming to follow standard email security practices, and with the referenced rejected email this shows that they are not honouring their own email verification methods.

This means that the mails sent in to LCC are failing the DMARC checks as seen, however this isn't something that we would simply allow as a bypassed security measure due to the nature of the content which can come in via adobesign.

As an organisation, we are subject almost daily to phishing and scam messages which often use methods such as AdobeSign, DocuSign, etc. as their main carrier, as such it is far too risky for us to allow these check to be ignored.

The correct method for this to be fixed lies with Adbose themselves, but unfortunately as a team who don't use the product, we don't have accounts with Adobe to be able to contact their support and offer the referenced example to them.

Can anyone assist on a workaround as we need to send out paperwrok quarterly to them.

Thank you.