check that your attribute name matches attribute-type I think you should pass "attribute-type" : "MyAttributes" and pass attribute state and content-state to match your attribute

you can run Option + Cmd + Enter to preview as canvas

this issue still persist unless restart physic device so it can start for simulator work fine

I am also facing the same issue in development I tried using the same token that was generated with .p8 file now is fine in development on production I haven't test yet