In the event that your ring does not fit (and in the event that the error was not ours), you are entitled to a one-time free exchange, provided the following:
The ring is returned in new condition
The ring is not customized in any way (such as engraving)
The ring is not made with custom attributes (for example, a width other than the stated width in the specific listing, custom material combinations, etc.).
We have a Size Verification option here: