The property is not (it is impossible to be) blacklisted, and therefore it is extremely unlikely that you have been associated with them.
The reason for all the calls is your house is obviously the last known address for them, and so that is where the various companies will look for them.
The calls themselves will be annoyance, but if everytime once rings, you firmly explain they were tenants who have since gone, and, if you have anything, give them a forwarding address or phone number if you have it.
Gradually you should find the calls stop.
Likewise, return the mail unopened, stating on envelope the date they moved out.
The only thing you might need to watch for, is if any baliffs turn up. You do NOT have to let them in, and i would advise strongly not opening the door to them- some firms are act first and listen later and may not be keen to listen to your explanation.
Keep close to hand a copy of the rental agreement to prove they were tenants, and anything you have which proves they moved out, along with a copy of proof of your identity, record that show your car is yours etc.
If a baliff does show up, you canspek to them through the letterbox or upstairs window, and explain, and offer to show them your proof that you are not them, and they have gone.
Do not open a down stairs window to them, as they have the right to enter the property through any open door or windown they can access.
Hope that helps.