if the ball doesn't hit a bumper and I do not push a flipper button it stays on..
This happens only after the ball ejects from the saucer eject hole at the top?
And then hitting a bumper, using a flipper or activating another solenoid?
Does it do this from just hitting a bumper or using the flippers?
After the saucer eject, do the lights dim or flicker before the machine shuts down?
When it 'resets', does the game act as if you turned off the main switch on the bottom of the playfield cabinet and then switch it back on a few moments later? Is there that pause for setup like when you turn that switch on, with the beep? Like a quick computer boot?
I'm not a pinball guy, but I do know something about circuits and drawing too much power, or the effects of a ground fault error.
It could be the eject solenoid is drawing too much power and an immediate second hit to the bumper or a flip extinguishes the available power at the power board, and then trips the MPU to reset.
That Bally era of machines also had trouble with their power board stability.
Lights would flicker on bumper hits due to uneven or low power and regulation, and if the drop was too extreme, the game would reset. It would shut down and restart as if the main switch was turned off, pause, then on. (BTW, You don't want to toggle this switch rapidly like a kid playing strobe with a light switch because the surge current can blow a high current power supply. It's also good to use a quality surge protector AC strip or box to prevent damage from power spikes. The arcades around here always do).
First thing, I would make sure the ground wires are solid, not loose, and double check the ground pin at the AC wall socket and the chord for continuity (no breaks). Ground fault might be causing the high current coils (solenoids and relays) to "act like an open circuit" with backup at the power supply secondary.
Then check the wires at the eject and at the board.
Then check the eject solenoid itself.