Traceback (most recent call last):
  File "electrum\gui\qt\confirm_tx_dialog.py", line 119, in timer_actions
  File "electrum\gui\qt\confirm_tx_dialog.py", line 123, in update
  File "electrum\gui\qt\confirm_tx_dialog.py", line 641, in update_tx
  File "electrum\gui\qt\send_tab.py", line 315, in <lambda>
  File "electrum\util.py", line 483, in do_profile
  File "electrum\wallet.py", line 1873, in make_unsigned_transaction
TypeError: conversion from NoneType to Decimal is not supported