That is called graphic tongue.
It is of unknown cause, and is not harmful, and tends to come and go on its own.
Some think B vitamins will help.
Here is what the mayo clinic recommends for treatment
I use homeopathic calendula tincture, 5 drops in a quarter cup of water..rinse 3 times a day until relief then only as needed.
Of course your doc should see this hands on to make sure it is graphic tonuge..which is what it sounds like.
Use reply if you need to clarify
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