Error (Safety Library Parser): POU '...': Definition mismatch between the Safety Library '...' and the Standard Library '...'.
The library POU mentioned in the error message is defined more than once in the project because it is contained (with the same name) in two libraries: in an included library with safety-related data and, at the same time, in a standard (non-safety-related) library.
Remedy
Delete one of the suspected included libraries. For that purpose, left-click the library icon in the 'Libraries' tree (COMPONENTS area, 'Libraries' category) and press <Del>.
If the error is still reported, contact the technical support of Phoenix Contact.