Does unknowingly consuming the unlawful affect the acceptance of prayers or necessitate punishment?

A Muslim eating at his neighbor's house from unlawful wealth, believing it to be permissible, does not prevent his supplication from being answered, nor is he held accountable for it, due to the حديث (Hadith): "Indeed, Allah has pardoned for my Ummah their mistakes, their forgetfulness, and what they are coerced into."