Can i change the land with PWD depatment that i have acquired by mistake and contructed building?

Dear sir/Ma'am, PWD did a survey for the road in our village around 15 years ago. As per that survey some piece our land is used in the road construction and we got compensation for that also but when they constructed road they didn't follow the same survey and by mistake they constructed road on the land that we didn't sell to them (Its a mountain area) and at that time as per best of our knowledge we constructed a property by road which we thought is our land, unaware of the fact that we are constructing on the land which is surveyed by the PWD for the road. But this happened only after the road has been made by the PWD. They didn't follow the survey and took over land that didn't belong to them and we haven't received any compensation for that also. Now we got summon to demolish that property. i want to know what can we do now and if there is other way to make payment or replace land by providing land to the PWD i don't want to demolish the building. Because case is we and they also constructed building and road respectivelyon each others land without informing each other so can we change that part of the land.