dropping something
which is the more correct way to say you dropped your wallet?

財布が失うた。
財布が落としました。
財布が無くしました。

Question

dropping something
which is the more correct way to say you dropped your wallet?

財布が失うた。
財布が落としました。
財布が無くしました。

Answer

"財布を落としました。" or "財布を無くしました。" is correct. 
You need to use "を" instead of "が".
Because a subject is someone (maybe "I or you"), and the wallet is an object. 
Another way is "財布が無くなりました。". You can use "が", because a subject is the wallet in this case.

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