Diziness. Diziness at night in sleep?

Day before day night my mom had dizziness at midnight around 3AM in sleep. Then she asked me to give sugar, she had taken a spoon of sugar and then she got heavy sweat . after sometime she had relaxed for sometime and ok with it. After that next day morning my family RMP doctor treated and checked BP (it was Normal) and suggested to give for blood test and tyroid test. Tyroid was normal and sugar had after lunch 160. Actually the same dizziness in midnight had happened 3 years back for my mom. And now it happened, that time (3years back had tested all and said nothing, everything was good. That time she had taken a antibiotic tablet without taking food.(we thought it happened for that purpose ) but this time she didn't take any tablet and she had taken food at night . But I don't understand why it is happening sudden dizziness ??? Please do check my mom reports 🙏 and say what is the reason for having dizziness at night in sleep ???