Jan 26 (Reuters) - Users on retail trading platforms Charles Schwab Corp and Robinhood reported operational problems in the market session for a second day in a row on Tuesday, according to outage monitoring website Downdetector.com.

The cause of the glitches was not immediately clear.

There were 791 reports from customers of Robinhood, the fintech startup credited with helping popularize trading among millennials, with 85% of complaints about bad server connection and 14% users saying they could not log in, according to Downdetector.com.

More than 200 Charles Schwab users said they faced problems with the website and could not log in or place trades.

"Earlier this morning, we experienced an issue with bank balances not displaying accurately that has since been resolved. Trading functionality was not impacted. We apologize for any inconvenience this may cause our clients," a Charles Schwab spokeswoman said.

Robinhood did not immediately respond to Reuters' requests for comment.

The problems were the latest in a string of technical problems among retail brokerages, which have faced a massive surge in volumes over the past year after most platforms cut commissions to zero and as stocks rebounded from COVID-19 pandemic lows.

Downdetector on Tuesday also showed reports of outages at Alphabet Inc's Google, Zoom, Amazon Web Services and Roblox Corp and Verizon Communications Inc. (Reporting by Noor Zainab Hussain and Niket Nishant in Bengaluru; Editing by Ramakrishnan M.)