Technical Electrical problems

[Anne E]

My 2017 500 pop just conked out, towed to garage, then auto electrician fitted immobiliser coil and part ignition barrel I think. He said the time and date couldnt be reset unless Inoaid almost £500 but still might not be the problem. Car does start but intermittently, and now start/stop light and triangle showing. I called him back asking had paid £160, he said it worked when I git it back, and now saying it’s the bcm It’s only clocked up 32000 miles. Can anyone help me or advise as not sure who to trust.
Thanks from an old lady who knows nothing about cars

 

[John202020]

Hi welcome did the car stop, whilst, driving, ie glide to a stop?
Put the key in and turn on ignition, wait, does the immobiliser light go out? Now crank to start? What happens?
Time and date "should " be a simple fix, I believe using the radio buttons
Has the car had a new battery you know of, has the car had, the engine earth strap replaced ( £5 part, plus fitting )?
Ignore stop start light for now, once running is there any messages on the display noting they disappear seconds after starting, about 10 or so.
There's a possibility that water has got into the body computer, this can happen if the drains are not cleared at least once every year under the bonnet