So, go into the entry in LastPass and edit it. Then click on the little wrench at the bottom to edit the form fields. Delete all of the fields. There will be one called "password" and the value it has is the dots. LastPass is getting confused by two fields, both called "password", one being the "real" password on the main part, and the other being the "form field" also called "password". So the solution is to delete the form field version.
A lot of other sites that have weird login form behavior can also be attributed to LastPass "over capturing" all of the form fields (many not visible) on a login page. This is also an issue where (bank sites) they replace your login ID with some sort of masked version that replaces all bit the last three characters with dots, just like the password as well as various checkboxes like "save my login/user ID". Most times, I turn that off, and then go into the LastPass vault entry and delete all of the form fields, except for one I want to keep (like language or country selections).
Also, make sure your browser isn't also sticking its fingers into the soup too by saving your login information as well as LastPass. Turn it off and make sure LastPass is the only place saving and supplying your passwords. So they don't get changed in one place and not the other, or they get hacked/stolen from the other place and LastPass has no way to know that happened.