Have you checked you aren't having both 'bucket', 'jar' terminology conflated here.
You can have USD Jar (inaccessible by card) and USD Balance (accessible by card)
I do note that they have recently improved the money transfer functionality within the app to/from Jars. Originally you could only go from same currency balance to same currency jar. Now you can also change currency like inadvertently go from an Accessible AUD to Inaccessible USD jar.
I'm currently in Europe using Wise without issue.
I did get caught when an Australian merchant incorrectly processing a AUD subscription which I had cancelled. I had nothing in AUD so the right thing was that Wise took it from 2-3 currencies where I had small amounts intending to use. When the vendor refunded the AUD it just goes back to AUD and will incur another transfer fee when it comes time to use it. Annoying.