US troops serving in elite units such as the Navy SEALs are increasingly forced to tap into their own money to buy crucial gear like helmets, GPS trackers and medical supplies as the service fails to supply them, a group complained to lawmakers.

There may be a systemic problem in the supply chain, said Rep. Duncan Hunter, who is a Marine veteran, after the meeting held at the Capitol Hill last week, Stars and Stripes reported.

“It’s been impossible for me to find out how the money is getting stopped and why it is not going down to where it’s supposed to be,” he said.

The problem may become a major issue should the US ramp up deployments back to the heights seeing at the peak of wars in Iraq and Afghanistan, said Rep. Adam Kinzinger, R-Ill., an Air Force combat veteran.

One of the people participating in the meet was Sean Matson, who retired from the SEALs and now heads a military supply company. He said the military measured his head four times before each deployment with plans to provide him a more advanced ballistic helmet, but it never materialized. He and six of his fellow SEALs each spent about $900 to get their necessary gear.

Aaron Negherbon from the nonprofit group Troops Direct, which steps in and delivers military supplies to troops that they cannot acquire through regular channels, said equipment as crucial as tourniquets or sniper gear may not be provided in time by the military supply chains.

“They came to us for…batteries because they didn’t have any of those … It is kind of like, ‘What the heck is going on?'” Negherbon said.