It seems that you are having erythema annulare centrifugum.
Mostly there may not be any cause.
But, some time there may be some cause.
Certain food like tomato, contact dermatitis
, infections, drugs like chloroquin, penicillin, finasteride
Vitamin D, steroids , immunomoduators may be helpful.
Local application of calcipotriol
cream may improve the lesion.
Still, you consult dermatologist
I hope you got my answer.
Dr. Ilyas Patel MD