Meriva A 2007 won't start

My car is a meriva A 2007 plate, bought in 2019 second hand, has driven fine until recently, last Thursday we were sat at traffic lights and the car cut out, no warning lights at all and no hazards. When turning it back on there were no lights on the dash, it would try to turn over but wouldn't start.  My husband found it could be the ignition switch so changed it the next day.  Drove fine until Wednesday evening when it cut out again, did the same but this time we could put the hazard lights on unlike last time, interior light worked, windows went up and down so battery isn't dead.  Was fine again until today, my husband did the school run fine, came back and checked all the earth ports, wiring, fuses, cleaned battery terminals and was fine, went into town shopping for 2 hours, came back and the car had nothing at all on the dash, tried to turn over but wouldn't, interior light worked, windows worked and hazards but this time it has completely gone, will not start even after trying for more than 4 hours! Can anybody help? Anybody else experienced this?

Edited November 3, 20223 yr by sazpol2014
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