Robinhood Markets is building up its phone-based customer service amid growing scrutiny over how the brokerage handles questions and complaints.

The Menlo Park, California-based firm will add live phone support for a broader range of situations, including trading and transfer issues, according to a blog post Monday. App customers can now ask to speak by phone to a registered financial representative for help with certain options trading situations, the company said.

Politicians are taking a closer look at Robinhood’s popular free trading app, including its role in last month’s investing frenzy involving GameStop Corp. and other “meme stocks.” Robinhood Chief Executive Officer Vlad Tenev faced more than five hours of questioning as a witness at a congressional hearing last week devoted to the episode, which also touched on the firm’s limited access to live phone representatives.

The company said that it will more than double the number of full-time registered representatives this year, expanding to new locations in the process.

“We believe great customer service incorporates a combination of real people and the best technology, and we continue to invest in both,” Robinhood said in the blog post.

Phone support hasn’t always been a part of Robinhood’s strategy. Although the firm had a number for customer service years ago, it was removed, Bloomberg reported in October. Recent episodes brought the issue to light. Some Robinhood users panicked last year when cyber criminals drained funds from their accounts, and they found there was no emergency number to call.

U.S. Representative Sean Casten, a Democrat from Illinois, brought up the firm’s customer-service strategy during last week’s hearing. Casten asked listeners to put themselves in the mindset of a Robinhood customer with an urgent question, trying to call the company.

“Let’s call, and let’s listen,” he said. He then played a recorded message directing callers to Robinhood’s website or app for support.

Robinhood has begun to realize the importance of adding live phone representatives. In January, for instance, some customers exercised worthless options contracts, resulting in immediate losses, when they could have simply let the contracts expire. Users are now required to speak to a registered representative in such cases, Tenev said in his prepared remarks for the congressional hearing.

And, as of last week, the company extended live phone support to customers with account-security problems, according to the blog post.

“We want to make sure we’re there for customers, especially in time-sensitive situations,” Robinhood said.