I have a aimilar problem with being banned from a former workplace, however my situation is this. I have been working at a daycare for over twelve months and once I received my qualifications and my contract ended they terminated my employment saying it wasn't in their budget to keep me as a qualified educator (cert 3 as required in my contract to obtain within the twelve months). To supplement my low income I have always babysat and done pick ups and drop offs for families that ask and give management permission to do so as many former staff still do but a week following my termination they told me when I went to collect a child on behalf of the parents that I was not permitted inside or on the premises and they would be telling parents they are not allowed to ask me to do collection of a child anymore and have given no reason for this. Do they have that right and what rights do I have since they are interfering with my potential to earn an income? Im also concerned they won't pay me my redundancy package of six weeks pay.

First, its not a good idea to piggyback your question on another thread. To avoid confusion I've moved your post to its own thread.

Yes, they have the right to control who has access to their facility. They can't tell a parent that you are not allowed to collect a child, but they can tell a parent that you are not allowed on their premises, which effectively does the same thing. They are not interfering with your ability to earn income because you can go to work at other daycare facilities.

However, telling parents you are banned without giving a reason, might be considered defamatory. But I doubt if its worth taking them to court over.

Are you sure that there isn't more to this story? Seem to me that the daycare center is also making it difficult for their clients which could result in their losing clients, and it escapes me as to why they would want to do that. Were there any disputes with the employer while you worked there or at the time that you left?
Did you expect or were you promised a pay increase upon completion of certification? Could you have remained there at the same pay level?