A bug happens in the Footer and the code keeps appearing

On this WordPress site with the Newspaper theme, the footer appears and looks normal (as you can see in https://www.vendaonline.pt/), but I installed a question plugin (DW Question Answer) and on the pages corresponding to the content of each subject, keep the footer with bug (https://www.vendaonline.pt/foruns/teste1/). The problem happens only on pages dedicated to the individual subject only. Can anyone help me solve the problem? enter image description here enter image description here