I know it's been a while, but I had the same issue and I have found some explanation to this thing on this link.

The term used in photography is "Purple fringing" and the reason why I "dug" more and tried to understand the issue is that I don't think is a sensor issue (in my case and probably in your case also) because I experienced something like that with a brand new camera and lens - Canon 80D and 50mm f/1.8 lens.

You can see also my photo attached.

I hope it helps, even though it's been a while.

I know it's been a while, but I had the same issue and I have found that it is called "Purple fringing" (Wikipedia).

The reason why I "dug" more and tried to understand the issue is that I don't think is a sensor issue (in my case and probably in your case also) because I experienced something like that with a brand new camera and lens - Canon 80D and 50mm f/1.8 lens.

You can see also my photo attached.

I hope it helps, even though it's been a while.