Thanks for taking the time to report this bug.
Bugs happen, that's a fact of life, in the real world, or in software.
With your help, we can eradicate bugs (from software, namely, this game).
First the bug must be replicated in our state-of-the-art testing facility. Once this has been achieved, a fix for the bug will be delivered to all those affected or unaffected. Please use as much detail as possible to describe what happened - if you have a screenshot or video of the problem that is even better!
Unfortunately, through squashing old bugs, newer bugs may be created in its wake. This is a never ending struggle.
Please post details of the bug below, with links to any screenshots or gameplay video you may have.