Problem in Ponceau staining after protein Transfer

Very recently I noticed that even if I have enough protein on the gel, enough to be detected by commassie stain- I do not get it stained by Ponceau on the blot after transfer. The protein gets transferred completely and the bands are visible after the western. I also ensured that the protein does not get lost due to over transfer. Western is working quite fine, initial protein concentration is good enough up to 50ug total protein, total transfer of protein does take place, there is no heating up during transfer, pH of the buffers are fine - I do not understand what might be the problem.