A lot of times people who are done playing for awhile will sell their accounts to someone buying any and every account. Then when the come back they recover it. Or the seller is a POS and recovering to resell under a different name.
Not a ton you can really do about this sadly =/
My suggestion would be to create and train your own accounts with bots or vennys. Find someone selling training services and just make sure you mule anything of value off the account to prevent a sticky finger'ed venny from lifting it. Generally speaking it will be more expensive but if you don't provide them the recovery information you can recover your own account.
Sadly because Jagex can't do anything correctly account recovery is a fucking joke, it is extremely easy to mass recover accounts and resell for a profit then rinse and repeat once enough time has passed to fend off the negative feedback you leave on the seller.
tldr: not much you can do, create and train/pay to train your accounts to avoid account recovery. Anyone who says they are legit and has good reviews you still run the risk of recovery from the original owner.