ERISA has it’s own set of rules and regulations and is unlike normal insurance that is governed by State laws and the Texas Department of Insurance.
Here is a 2019, opinion from the Eastern District of Texas, Sherman Division, that deals with ERISA and a claim for Long Term Disability (LTD) benefits. The opinion is styled, Xien Huang Napodano v. Ericsson Inc. Short Term Disability Plan.
On August 22, 2017, Napodano resigned from his job by leaving a note on the desk of his boss and a few days later applied for LTD benefits. He was informed that he had to first apply for Short Term Disability (STD) benefits first, before being eligible for LTD benefits. He then filed for STD benefits.