thank you. In terms of the judgement that has been rendered against you, based upon what you say, you did not receive the original claim papers, have at least a reasonable prospect of defending the claim and finally are acting in good time having discovered the judgement that has been made against you. Accordingly, he would have grounds to apply to set aside the original judgement following which, or the enforcement action that has been taken will fall away.
In terms of making an application to set aside the original judgement, you would need to initially apply using form N244. I'm attaching an example of how to complete this form and how to prepare an associated witness statement which you can use to adapt for your own application.
there is a fee of £255 to pay with your application and if it is your intention to apply, then you should make it a priority not to delay as delay can be prejudicial to your application in its own rights. In addition to the above enforcement action falling away, if your application is successful, the CC J which has been registered against you will be removed restoring your credit file to its former status.
The entire claim will then be reset to the pre-hearing state and you have an opportunity to enter a defence and defend yourself. Depending upon the terms of your tenancy agreement, it may be that you would need to consider joining in the landlord as a defendant by way of a counterclaim in respect of any claims that have been raised against you in the event that the claimants themselves are legitimate in which case it may be that you would have a claim against the landlord for indemnity failure to provide you with a permit as the landlord from what you say has granted you a right to Park in the allocated space