GameStop's stock price remains sky-high, but shares are becoming more difficult to buy.

On Thursday morning, Twitter users began posting screenshots of their Robinhood app that showed a message appended to the stocks of GameStop, AMC, Nokia and Bed, Bath and Beyond: "This stock is not supported on Robinhood.".

On Thursday morning, GameStop shares spiked to $467 but then crashed to $126 as investors were unable to purchase more shares.

Rashida Tlaib, a Democrat from Michigan, called on the House Committee on Financial Services to hold a hearing on the trading service's actions and describing Robinhood's efforts as "market manipulation.".

An image circulating on social media Wednesday showed an apparent warning from TD Ameritrade saying it put restrictions on the trading of stocks for GameStop, AMC and others

Nasdaq CEO Adena Friedman told CNBC on Wednesday that if there is any market manipulation going on, it may halt the trading of a stock to investigate

AMC is listed on Nasdaq, while GameStop is traded on the New York Stock Exchange. 

William Galvin, secretary of the Commonwealth of Massachusetts, told Barron's on Wednesday that he thinks the New York Stock Exchange should "consider simply suspending it for a month and stop trading it." 

The Securities and Exchanges Commission, which oversees the stock markets, told The New York Times it's watching "internet chat rooms for signs of potential market manipulation." 

The firm put certain restrictions in place for GameStop and AMC stock, but did not ban them