Account Migration - All business email from 2*** lost in the process of migration

I am not happy at all with the level of service I've received from 1-Grid at the moment. In 2012 I asked for my account to be migrated from my reseller to me and this never happend inspite of numerous emails. There has been a constant back and forth whenever I've had a fault sorted out this issue would rear its ugly head. Fast forward to April 2021, someone decided to finally take decisive action. I am happy that the account has now been migrated and officially belongs to me, however, in the process as a business I have lost all emails, contacts, client names and emails, important documents, from 2016 to 2020. I run a recruitment agency and we constantly receive emails and documents from clients, all that data/information is now gone. The consultat that assisted with the migration promised to look into the matter two days ago and never came back to me and does not even respond to my emails. You send a message on WhatsApp they never respond the chat line is even worse. As soon as I find a reliable and professional service provider. I will definately terminate my contract with 1-Grid!!!