鉄壁 てっぺきじゃありませんでした
teppekijārimasendeshita

Noun
Desu Copula
no-Adjective

The polite, past negative form of 鉄壁

1. Was not impenetrable.; Was not solid as a rock.; Was not a strong defense.

Past/Perfective
Negative
Polite
Terminal Form