It is true that enlightened people may contradict each other. In simple words, the reason for such apparent contradiction is the presence of vasanas, which are not harmful to the realization, in those people. And those people may not eradicate them voluntarily.
This answer is totally based on the words of Dattatreya from chapter 19 of the scripture named Tripura Rahasyam.
#1: Different behaviors by enlightened people may lead to apparent contradictions
Although the state of moksha is the same for all enlightened people, they tend to exhibit different behaviors, which sometimes lead to contradictions. The following words of Dattatreya clarify this. Dattatreya enumerated a list of enlightened people with different sorts of behavior.
O Scion of Bhrighu's lineage! There are apparent differences in the
characteristics of Jnanis, caused by the aspects and attitudes of
intellect and the varieties in its activities. Such differences are
quite obvious in Brahma, Vishnu and Siva who are Jnanis by nature.
That does not mean that jnana admits of variety. These attitudes
depend on their vasanas (dispositions) and environments. They are
Lords of the universe and all-knowing. Their jnana is pure and
uncontaminated by what they do. Whether a Jnani is fair or dark in
complexion, his jnana neither shares these qualities nor the qualities
of the mind. See the difference in the three sons of Atri, namely,
Durvasa (said to be of the aspect of Siva and reputed to be
exceedingly irritable), Chandra and myself (Dattatreya, of the aspect
of Sriman Narayana or Vishnu, reputed to be the ideal of saints,
roaming nude in the forests, etc.). Vasishta never fails in the
strictest adherence to duty as prescribed by the scriptures; whereas
Sanaka, Sananda, Sanatsujata and Sanatkumara are types of ascetics
totally indifferent to any action, including religious rites; Narada
is the ideal of bhakti ; Bhargava (Sukra, the well-known preceptor of Asuras, who incessantly fight against the gods) supports the enemies of the gods,
whereas the equally great Sage Brihaspati supports the gods against
their enemies; Vyasa is ever busy in codifying the Vedas, and in
propagating their truth in the shape of the Mahabharata, the Puranas
and the Upapuranas; Janaka famous as the ascetic-king; Jadabharata
looking like an idiot; and many others.
It is evident that Sukracharya contradicts gods. And there are also different behaviors between the realized people. The sole reason is that some kind of vasanas can continue after self-realization also.
#2: Enlightened people do not care about the vasanas they possess as they are not harmful to the realization
There exist certain kinds of vasanas that are not harmful to the realization. Those vasanas are called kama vasanas or vasanas of desire.
Sages with subtle and clear intellect have not considered it worthwhile to eradicate their desire, etc., by forcing other thoughts
to take their place, because desires do not obstruct realisation.
Therefore their desires continue to manifest even after realisation,
as before. Neither are they tainted by such vasanas. They are said to
be emancipated and diverse-minded. They are also reputed to be the
best class of Jnanis.
The vasanas not inimical to realisation are not weeded out by the best
class of Jnanis because they cannot seek new ones to crowd the old
out. Therefore the old ones continue until they are exhausted and thus
you find among them some highly irritable, some lustful and others
pious and dutiful, and so on.
Thus the enlightened people can differ in behavior and other aspects due to the kama vasanas. It is important to note that this answer does not contradict the other answers as the kama vasanas can be due to niyathi. You can observe it from the first quote of this answer.