Your problem is more likely due to,
1,Use of deodorant in the past.
2,Shaving with common soap.
in under arm in the past or having at present.
Now stop use of deodorant as you have done.avoid waxing,you can shave but with shaving cream,wear cotton clothes,take treatment for fungal infection if it is there,
You can apply triple action cream containing antibiotic,anti fungal and steroid
. You can apply lacto calamin lotion.
It will take time but you will get result.