Gents, (I hope this is in the right area....)

I've recently purchased a Garmin AusTopo 2689LMT. I had been using Garmin AusTopo Maps V5 (on a MicroSD card) on my old Garmin 1490T. I was hoping to be able to just remove the SD card and insert it into my new 2689LMT and I would have AusTopo maps on my new GPS. I tried this without success, does anyone know of how to make this work or a work around to make it work on my 2689 or do I have to throw the AusTopo's in the bin so to speak??

If I can't use the AusTopoV5 that I have, what's the next best thing (preferably not that costly) I can do to have AusTopo on my GPS?