-ριθμός should be αριθμός

and

https://www.wordreference.com/gren/παραβολο


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Note added at 19 mins (2022-07-01 06:18:33 GMT)
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See this example:

The next step is to fill in the administrative fee number. This fee costs 300 euros, has a code 2108 and can be issued either electronically or via (KEP)
https://g2red.org/wp-content/uploads/2021/04/3.-Parents.pdf




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Note added at 36 mins (2022-07-01 06:36:04 GMT)
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Also see:

e-Administrative fee
Ανακοίνωση - Ενημέρωση. Από την Δευτέρα 21/2/2022 η πλατφόρμα e-Παράβολο εκδίδει «κωδικούς πληρωμής» σύμφωνα με το πρότυπο RF για την πληρωμή των ..
https://www.gsis.gr/en/citizens-businesses/payments-proceeds...