An insurer may not engage in any retaliatory action against a physician or health care provider, including terminating the physician’s or provider’s participation in the preferred provider benefit plan or refusing to renew the physician’s or provider’s contract, because the physician or provider has:

(1) on behalf of an insured, reasonably filed a complaint against the insurer; or

(2) appealed a decision of the insurer.

See https://statutes.capitol.texas.gov/Docs/IN/htm/IN.1301.htm