No citation generator is perfect - especially against user error. If you give a citation generator incorrect information, it will probably give you an inaccurate citation. Check your input information carefully as you enter it to ensure the accuracy of the final product.
You will save yourself a lot of time and trouble by copying preformatted citations from various databases. Many, but not all, databases will offer a citation formatted according to MLA. Look for a link or icon called "cite", or "citation", or sometimes just a quotemark ("). Always check your preformatted citations against the MLA 8th edition cheatsheet, because the citations are done by computer, not by a human.
Here is an example from the EbscoHost database showing the citation icon at the far right-hand side:
Click on the "Cite" icon, then choose "MLA":
After copying and pasting the citation into your Works Cited page, you would check the citation against the MLA cheatsheet to verify that it is correct.