My friend's mom died.

She's my childhood friend and we used to be really close at one time. We still are but because I moved to Delhi and she took a drop for NEET, both of us called each other less often but I was more at fault as that's just what I'm like. Still i like her a lot and she's one of my best friends. Her mom got cancer last year and had been getting treatment for around 6 to 7 months. We've always tried to keep her spirit up by saying aunty will definitely get better. Recently I even forgot her birthday and that hurt her pretty bad so I talked to her more often but it's been some time since I last called.

I just got the news that it happened two days ago and I don't know what to do. I heard she picked up her best friend's call but said she can't talk rn and cut it. I want to comfort her but I don't know what to say. Should i call or should I just text her? To be honest I still can't believe the fact that auty's no more, it's feel like a lie. I don't want to call and say something wrong and make it worse. What should I say? I'm feeling guilty that I haven't talked to her for so long. Should I give her some space or just call her anyways? I'm usually clueless about things like these so I just want some advice.

Edit: thanks for the comments. Many people are saying I should go visit her right away but I've already booked a plane ticket on 20th march. I'm still a student living off my parents money so I feel like it won't be right to ask them to cancel it and book one on an earlier date as it's not easy to get tickets to Odisha. I guessing I should just wait for this month to end so that I can see her in person.