HB 4123 requires the Texas Health and Human Services Commission (HHSC) to provide written notice to Medicaid providers at least 120 days before their enrollment period expires. The notice must include the expiration date and detailed instructions for revalidating enrollment. If a provider submits a revalidation application at least 60 days before expiration, HHSC must conduct an initial review and notify the provider of any deficiencies at least 45 days before expiration. Providers will then have at least 10 days to correct deficiencies and avoid disenrollment. The bill applies to Medicaid providers whose enrollment expires on or after January 1, 2026.