Bolzano to Canazei

You can use the Suedtirol Mobil route planner.
https://www.sii.bz.it/en/

Looks like the last bus is at 15:23.

Are you coming from somewhere else?

It may be difficult to find bus timetables. But remember that Canazei is not in South Tyrol but in Trentino, so there are much more services under trentinotrasporti.it

The main valley line runs from the railway station of Ora/Auer (that can be reached by regional trains, it is between Trento and Bolzano) to Cavalese, and then another bus runs to Canazei and Penia and runs till 8pm or so. But it is a long stretch.

Yes, im travelling from Vienna