Estate Agent didn't provide House Plans

I am Lerato Promise Madia currently residing in Savannah Country Estate in Pretoria Silverlakes. My partner (Solomon) and I bought this property in 2017 I think from an agent called Lyn Maxwell Andreou and the process went on smoothly no glitches at all. But recently we wanted to extend our house and realised we dont have the house plans, damn we were so stupid that we didn't request the plans from Lyn but we went to the Tshwane municipality to request the documents and we were given a time frame and they will call us to come fetch the plans when found

5 days passed and they finally called us to say they dont have the plans. Thats when we contacted Lyn to tell her that legally we were supposed to receive the house plans and she agreed into finding out about why the plans aren't at the tshwane offices. We explained that we cant pay for an existing plan that we were supposed to have in the first place. We gave her 3 weeks, she came and told us that they have found the plan, as happy as we were, we waited for her to give us the plan but a week passed without anything then today she tells us that the file has been lost. We need to engage with the council to get the lost plan. We ask her that has to be rectified because its not our problem she then dumps us and says we need to further correspond with her attorney going forward and she tells us with an attitude

I really need your advice on what to do because we cant be paying a whole lot of money for a plan that is supposed to be in existence. She needs to get a hold of the previous owners because we dont know them and she is the middle man in this whole thing. why communicate with her lawyer if its he job to provide us with one. A proper investigation has to be made because it's ******* to sell a house without plans and we want her to give us our house plan

Regards Lerato Madia