I am delivering a mandibular over denture with two Locators in the area of the mandibular canines [#22,27; 33, 43] . I first tried cold curing housing into place one by one chair side. That did not work. I then took an impression with impression copings in place, sent it to the lab for processing. That did not work either. The attachments are not engaging into the Locators. I tried replacing the attachments and used all the different colors and nothing. The denture seats and as soon as the patient does any movement the denture rises up. Not sure if the female Locators have something wrong with them. The denture on my lab models engages, but not in the mouth. I've checked it with PIP paste and can not find anything. What is going on? Any suggestions?