If idle is low cud it be the cause of the engine stalling.

And could all so be you turned the idle down,try turning it back up.

You may not be making enough power for the alternator to make the engine run correctly.

Check the dashpot so that when you take your foot off the motor slows down slowly with no dashpot or wrong setting , when you take your foot off for a fraction of a second you have air only, not gas and air, hence motor dies