Need more data but the plans I see on my account is different from what I saw from the website

So I have this plan, $45/ month with 2GB.

Recently I’ve been going over my limit so I do need more data, maybe just 3 more GB so I tried to change my plan but all the options I saw is starting from $65~ for 60GB, which I don’t need that much. There’s add-on but it charges $10 for 100MB which is ridiculous.

Then I went to Koodo’s homepage, then I saw $45 for 30 GB WITH rollover! I’ve been paying the same amount for a lot less data!  so my question is how could I change to THAT plan?? Is it for only new customers??