PSBT Serialization Issue Causing Signing Failures with Coldcard /BitBox

[cakesoft-swati]

• Description
  We are encountering an intermittent issue in the Keeper Desktop App (Live environment) while signing transactions using hardware wallets.
• The issue occurs with:

1. Coldcard MK4
2. BitBox

• On the device side, it continues loading and does not proceed further. On the desktop app, an error popup appears.

• Expected Behavior

  1. PSBT should be sent correctly to the device
  2. Device should sign successfully
  3. No HWI deserialization error should appear