Debuyer 36cm slightly warped upwards in the middle I realise now that I probably heated it a bit too aggressively to begin with and my largest ring isn't actually big enough for it neither of which will have helped. The warping isn't too bad though, though to stop the oil covering the bottom though. 

Is there a good way to go about fixing this or that just how my pan will be now? It's still usable for sure I just need to swill the oil about quite a bit.