她没有还我钱。

[connie.j.chi]

This sentence has the incorrect character, it should be
他没有换我钱

[slicedgorgonzola]

I believe in this case 还我钱 means to “repay” as opposed to “exchange”. See:

1. 令我惊喜的是，他立刻还我 钱 了。
2. 那你可以还我 钱 了吧？