I am working on a 3T3L1 cell line. I received my cell line with a passage number of 7. Cells were attached until the passage number reached 10. However, after that, cells began detaching from the sides of the flask, and by the 11th passage, cells were not attaching to the surface at all. Can someone guide me on what I should do? These are pre-adipocytes. I am maintaining the cell line in DMEM + 10% FBS and using 1x Trypsin-EDTA solution.