Defunct Seagate Hdd

Hello again. Despite the good advice from auggiedoggie and studiot last time, I splashed out for a Seagate Freeagent 500Gb external HDD. This was my whole backup ie about seven years worth of correspondence, photos,, scanned official forms etc. Due to inattention when using Paragon Hard Drive Manager, I have managed to delete the partition. It is now inaccessible. Does anyone out there know how to resurrect it? Paragon HDM says it can't undelete the partition and Seagate are asking GBP£400-£600 (or USD$800-$1200) to recover it for me. Happy Holidays by the way to all the community.