Cannot submit Condition 'Current order total'. Amount field is required.

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Problem/Motivation

When submitting the form for condition 'Commerce: Current order total' in the ECA module, I receive an error stating "Amount field required", even though the field is properly filled in. This prevents the submission from completing successfully.
Based on my observations, this issue is likely caused by a missing currency value.

Steps to reproduce

Navigate to the ECA and make a new Model.
Make an event, for example 'Checkout: Completion'.
Make an action, for example 'Send email'
Make an condition 'Commerce: Current order total'
Fill in all required fields, including the Amount field.
Submit the form.
Observe the error message: "Amount field is required" despite the field being filled.