Encoding::UndefinedConversionError

[DenniWittig]

Hello,

I get an error for my fints account (n26 is working fine).

This is my config.yml

ynab:
access_token: "d1e******"
budget_id: "4fe******"
accounts:
- dumper: :n26
iban: "DE2******"
ynab_id: "adb******"
username: "******"
password: "******"
- dumper: :fints
iban: "DE2*****"
ynab_id: "65f******"
username: "4******"
password: "******"
fints_blz: "17054040"
fints_endpoint: "https://banking-bb6.s-fints-pt-bb.de/fints30"

And this is the Error Message I‘m getting.

docker-compose run --rm importer
Traceback (most recent call last):        8: from /usr/app/run.rb:9:in `<main>'
        7: from /usr/app/run.rb:9:in `map'
        6: from /usr/app/run.rb:11:in `block in <main>'
        5: from /usr/app/lib/account.rb:18:in `fetch_transactions'
        4: from /usr/app/lib/dumper/fints.rb:22:in `fetch_transactions'
        3: from /usr/local/bundle/gems/ruby_fints-0.0.3/lib/fints/client.rb:79:in `get_statement'
        2: from /usr/local/bundle/gems/ruby_fints-0.0.3/lib/fints/helper.rb:13:in `mt940_to_array'
        1: from /usr/local/bundle/gems/cmxl-0.2.2/lib/cmxl.rb:36:in `parse'
/usr/local/bundle/gems/cmxl-0.2.2/lib/cmxl.rb:36:in `encode!': "\x84" from TIS-620 to UTF-8 (Encoding::UndefinedConversionError)

I hope you can help me out.

Kind regards,
Dennis