Relocation means that there are bad sectors in your HD, but disk companies has a limited solution for that. They reserved some sectors at the disk to replace these bad sectors so these bad sectors are relocated, and instead of these bad sectors the reserved sectors are used. But as time goes on these bad sectors will increase and all the reserved sectors will be used.
Then you will start to face bad sector problem.
There is simply no solution for that, you can continue to use this hd for some more time at your own risk. But eventually the disk will be unusable. So I would recommend you to backup the data at the disk ASAP, then it is up to you to continue to use the disk or not.
By the way now your disk getting slower, as it needs more time to reach the data at the relocated sectors.