でたらめでわありませんでした
出鱈目ではありませんでした
detaramedewārimasendeshita

Noun
Desu Copula
na-Adjective

The polite, past negative form of でたらめ

1. Was not nonsense.; Was not arbitrary.; Was not fabricated.

Past/Perfective
Negative
Polite
Formal Register
Usually Written in Kana