Hello,
Thanks for posting your query.
The sticking together of skin where it touches each other near the folds is commonly seen due to excessive sweating. Sweat or perspiration often feels sticky if you sweat profusely or let the sweat dry on your skin.
The other possible causes can be an overactive thyroid gland, low blood sugar, hyperhidrosis and withdrawal from certain narcotics.
I encourage you to consult your dermatologist for proper diagnosis and treatment.
Treatment includes botox shots, anti perspirants and iontophoresis depending on the severity of the problem.
Meanwhile have plenty of fluids and try to wash your skin often. You can use an antiperspirant powder in the area too.

I hope this answers your query.
In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.
Please accept my answer in case you do not have further queries.
Wishing you good health.
Regards.
Dr. Praveen Tayal.

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