Editor’s note: This article by Patricia Kime originally appeared on Military.com, a leading source of news for the military and veteran community.

A Washington state lawmaker is seeking answers on the problematic transition this month of the Defense Department's contract for managing the Tricare West Region.

Rep. Marilyn Strickland, D-Wash., sent a letter Thursday to the Defense Health Agency saying the issues with new contractor TriWest Healthcare Alliance were hurting military readiness.

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Strickland said she has heard from dozens of constituents who have been frustrated by poor communications and the process of getting medical care.

"The combined effect of this mismanagement has led to canceled referrals, appointments, and even surgeries," Strickland wrote in her letter to Acting Principal Deputy Assistant Secretary of Defense for Health Affairs Dr. David Smith and Lt. Gen. Telita Crosland, Defense Health Agency director.

"Ultimately, TriWest's lack of preparedness and the Defense Health Agency's lack of contract oversight are actively harming military readiness and the lives of our service members, families and retirees," Strickland wrote.

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Beneficiaries and health care providers began raising concerns in December about the transition, shortly after TriWest published a new directory that did not include many providers under the previous contractor, Health Net Federal Services.

As a deadline approached for beneficiaries who pay for coverage by debit, credit card or bank transfer to update their payment information, many encountered trouble with the TriWest online portal or waited hours on hold to conduct business.

The original deadline of Dec. 31 to update information has been extended twice, with patients given until Feb. 28 to complete the process. They will lose coverage backdated to Jan. 1 if they fail to update their information by that date.

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"Despite the extensive difficulties documented by beneficiaries in contacting TriWest customer service and website problems, the current plan to disenroll beneficiaries who cannot establish a recurring payment is untenable," said Strickland, whose district includes Joint Base Lewis-McChord, home to nearly 300,000 personnel, military retirees and their families.

Earlier this month, TriWest officials told Military.com that they have adjusted staffing levels at their call centers to deal with the increase in volume and that hold times were decreasing.

Among the changes is an option for callers who have been on hold for at least 15 minutes to request a callback.

"But the quickest way for a beneficiary to make a payment or view enrollment information is through the secure, self-service beneficiary portal," TriWest said in a statement Jan. 6. "Several improvements were recently made to the portal to help enhance the beneficiary experience." 

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Strickland also raised concerns about TriWest's range of health care providers. The company says it has a network of nearly a million, but some providers under Health Net have reported that they have faced problems getting approval to join TriWest's network.

Strickland has asked for data regarding the number of beneficiaries who may lose coverage, a timeline for improved communications, and any plans for ensuring that patients get continuity of care in the transition period and beyond.

"I urge you to rapidly work with TriWest Healthcare Alliance to implement timely solutions that ensure our service members, families and retirees are treated fairly," wrote Strickland, a member of the House Armed Services Committee.