Robinhood Markets the online trading platform, has agreed to pay $29.75 million to settle regulatory probes by the Financial Industry Regulatory Authority (FINRA). The settlement includes a $26 million fine and $3.75 million in refunds to affected customers.

The fine from the broker-dealer industry regulator comes on the heels of a separate $45 million settlement by Robinhood Securities and Robinhood Financial in January with the US Securities and Exchange Commission, which accused the retail trading firm of failing to preserve records and not reporting suspicious activity on time, among other problems.

“Today’s action reminds Finra members that compliance with core regulatory obligations remains critical to safeguarding and serving all investors,” Bill St. Louis, Finra’s head of enforcement, said in a statement.

Robinhood, which made its name bringing commission-free trades to retail investors via a smartphone app, didn’t admit to or deny Finra’s claims.

Among other allegations, the regulator said Robinhood failed to supervise social media influencers paid to tout the firm and some of the social media communications were misleading to investors.

The firm also fell short on compliance with reporting obligations for data files called blue sheets, which include detailed trading information that regulators request to investigate suspicious trading.