LeBron James -- Samsung Scrambles Emergency Team ... After Pitchman's Cell Phone Craps Out

When LeBron James tweets, Samsung listens ... especially when he's complaining about a HUGE problem with his cell phone -- since LBJ is a pitchman for the company.

The drama began earlier today when 'Bron tweeted, "My phone just erased everything it has in it and rebooted. One of the sickest feelings I've ever had in my life."

We spoke to a rep for Samsung who essentially told us the company scrambled the jets to remedy the problem that blasted to LeBron's 12 MILLION followers.

"We are following the situation," the rep tells us ... "We have a team looking into it. There should be more information soon."

LeBron, probably realizing he made a pretty huge boo boo, deleted the tweet ... and replaced it a short time later with some new info: "Close call. Wheew! Got all my info back. Gamer! Lol."