You were wrongly accused: examine false accusation under Section 297 StGB.
Whoever knowingly falsely accuses another person of an offence prosecuted ex officio and thereby exposes them to the risk of official prosecution may fulfil the offence of false accusation under Section 297 StGB. Unlike the honour offences, false accusation is an ex-officio offence prosecuted by the authorities.
From a legal perspective, clean documentation matters: what was alleged, to whom, and did the reporting person know that the allegation was false? These questions shape the legal assessment.