This is just a question.
Western Sahara has grievances against Morocco- whether legitimate or otherwise.
Palestine has grievances against Israel-whether legitimate or otherwise.
Biafra has grievances against Nigeria -whether legitimate or otherwise.
Buhari has thrown the weight of the Federal Government of Nigeria behind the first 2 agitations., and has ignored the problem he has in his own backyard. Biafra/IPOB is a national security threat that could be exploited by any power that wants to destabilize Nigeria.

So 2 questions arise:
Why would Buhari fight injustice in Morocco, and Israel by supporting the self determination struggles for Western Sahara and Palestine but not support the same for Biafra as it fights the purpoted injustices in Nigeria?
Why is Biafra/IPOB not seen as a national security threat and addressed properly rather than as a fight between PMB and Nnamdi Kanu.

These are issues that require a complex arguments. If you have to resort to ethnic banter, you've already lost the argument.

looks OP doesn't know how evil Islam is