Not only has your landlord failed to register the car for a permit, it also looks as if you have failed to update the V5C Registration Certificate for your car. I suggest you check with the landlord why he has failed to do what he promised to do. It may be that the permit rules make the resident responsible for obtaining permits.
So with no permit, when you drove in during the restricted times, their CCTV registered a non-permit holder, and they then served postal PCNs to the V5C address as they are obliged to do by law. All subsequent enforcement documents must be sent to the name and address the council obtain from the DVLA. So why have you not updated your V5C ?
You have posted-up three Charge Certificates, but there would have been three postal PCNs served before these, so what happened to them ? Anyway, you can do nothing with the CCs except pay them, or ignore them and wait for the final part of the process which will enable you to get the matter reverted to the PCN stage, at which point you can either pay or submit representations.
At the end of the 14 day payment period on the CCs, the council must register the PCNs at the Traffic Enforcement Centre, (TEC). Only when they have done this can they instruct bailiffs to recover the money. Please note that there is no possibility
whatsoever of a CCJ. At this stage they will send out an Order for Recovery for each of the PCNs to the old address. But you can download the relevant forms from TEC, fill them in and submit them. The form you require is PE3
https://www.gov.uk/government/collections/traffic-enforcement-centre-formsSo you now need to become proactive, and phone TEC every 7-10 days to find out if the PCNs have been registered. Once they have, you can submit a Statutory Declaration for each one, stating that you did not receive the PCN. TEC then cancel the CCs and OfRs and the matter reverts to the PCN. You are still liable for the PCNs.