With new Apple (APPL) and Tesla (TSLA) stock splits going into effect Monday, some investors were ready to become active on trades. However, they may have found using investment programs difficult. It seems the rush to buy more stock in the popular companies slowed down several trading programs.

Apple announced that the board approved a 4-for-1 stock split on July 30, the first since 2014. Tesla announced a 5-for-1 stock split earlier this month. The move makes their shares more affordable, so investors were jumping to buy more stock.

“Through the first hour and a half of Monday’s session, Apple had traded 82.7 million shares, which is roughly 46% of the stock’s 30-day volume average of 178.588 million. Tesla shares had exchanged hands 37.4 million times, more than half of its 30-day volume average of 73.369 million,” CNBC reports.

Several trading programs were overwhelmed by the number of users logging on at once. Charles Schwab apologized after announcing that their website was completely inaccessible for some users on Monday morning, and Vanguard reported similar outages.

Robinhood noted that there were issues with “delayed order status updates,” but assured users that they were “display issues only, and should not impact order execution.” Their system is listed as operational on all fronts according to their status page.

TD Ameritrade also apologized for moving slowly Monday morning.

Users took to Twitter to complain about the outages and slow-downs. With prices rapidly changing, many are worried they’ll miss low prices on Apple and Tesla stocks.

Apple became the first US company to hit $2 trillion in market value
Apple became the first US company to hit $2 trillion in market value AFP / KIMIHIRO HOSHINO