Contradiction with Jeremiah 27:21
This verse continues the directive in Jeremiah 27:20, so it does not inherently provide a contradiction without additional context.
Jeremiah 27:21: Yea, thus saith the LORD of hosts, the God of Israel, concerning the vessels that remain [in] the house of the LORD, and [in] the house of the king of Judah and of Jerusalem;
Contradiction with Lamentations 1:1
Lamentations 1:1 speaks of desolation and destruction, contrasting with the hope of restoration implied in Jeremiah 27:20.
Lamentations 1:1: How doth the city sit solitary, [that was] full of people! [how] is she become as a widow! she [that was] great among the nations, [and] princess among the provinces, [how] is she become tributary!