They had to *provide* notice, but that doesn't mean you received it. Such notice can be done in many cases by "publlication"--basically, by publishing in the legal announceements or notices section(s) of local papers. IF they provided notice in the legally approved ways, you are deemed to have received it even, in fact you did not.On the other hand, if they did not provide notice in the proper way(s), then the taking of your property may be void. Retain an attorney to look  into how notice was provided and whether there were any defects in it.