Recover files affected by ransomware
So for the last 2 months our server was affected by a cyber attack. Our server is currently inhouse but our domain is hosted by our Government ITC Datacenter. The Government datacenter was hit during a weekend and it had affected our file server. So the only option the IT guys at datacenter gave was to format everything on our server and reinstall windows server 2016 which ended in our files being deleted as well. i have ran a data recovery software on our server and i managed to recover the data, but the thing is all files were corrupted, all files had file extension (zlj4i9). i have been trying for 1 month now to try and recover the corrupted file but was unsuccessful.
Is there anyway we can recover or decrypt the corrupted files?