The 75-year-old former military ruler was elected in 2015 after pledging to defeat Boko Haram Islamists whose insurgency has devastated the country's remote northeast since 2009.
But despite gains against the jihadists, unrest has intensified elsewhere, including a resurgence of deadly communal clashes between farmers and herders, kidnapping for ransom and banditry.
Last week, Amnesty International said 1,813 people have been killed in 17 of Nigeria's 36 states since the start of the year -- more than double the 894 killed in the whole of 2017.
On June 23, more than 200 people from Christian farming communities were killed in the central state of Plateau, renewing calls for more to be done to stem the bloodshed.
"The authorities have a responsibility to protect lives and properties but they are clearly not doing enough going by what is happening," said the group's Nigeria director, Osai Ojigho.