Buick service near Centennial, CO

My issue accured using my cruise control on the highway, as I slow down my rpms started idling, the only way to get it to was to barely tap gas and brake to get it stop. I called Pam asked if she know what the problem was got no answer. I called some places looking for a transfer case, pam finally returned my call said it was possibly the transfer case. She asked why I was going to take it to another shop when she would do it for 1000. I told I had 350 now and I'd get the rest in a couple days I dropped on a Monday a week an half before Christmas. I was told from the shop that it should only take 4-6 hours to replace. I didn't get my truck back until Christmas Eve. So not knowing what was really fixed, I took it to get oil change and they informed me my output transfer case seal is leaking bad and I need to take it back to who replaced it. Call the Pams business number it's temporarily disconnected.