Fairly new to straight razor shaving, about two months now. My first strop has been a new SRD 3 inch hanging strop that has been working out very well. About a month ago I also picked up a SRD 3 inch two sided paddle strop. I've treated the rough side with chromium oxide paste and have left the smooth side as is.

Here is my concern: Last night I was using the smooth side on the paddle strop and noticed something odd. My blade edge was not making full contact across the width of the strop. The center of the blade edge was in contact while the heel and toe portions of the edge had a very slight gap between the blade edge and the strop. This was apparent with several razors. This morning I laid a machinist flat edge across the width of the strop and the strop has a very slight hump in the center running the length of the strop.

What can I do about correcting this? The strop has been used and also treated with paste so returning it I feel is not in order. Is there anything that I can do to flatten the smooth side in order the have full contact with the blade edge?

I have been very careful in storage and the leather has not been subjected to any moisture. HELP