“…In recent years, the discussion of fractional initial value problems (IVPs) and BVPs have attracted the attention of many scholars and valuable results have been obtained (see ). Various methods have been utilized to study fractional IVPs and BVPs such as the Banach contraction map principle (see [8][9][10][11]), fixed point theorems (see [12][13][14][15][16][17][18]), monotone iterative method (see [19][20][21]), variational method (see [22][23][24]), fixed point index theory (see [17][18][19][20][21][22][23][24][25]), coincidence degree theory (see [26][27][28][29]), and numerical methods [30,31]. For instance, Jiang (see [26]) studied the existence of solutions using coincidence degree theory for the following fractional BVP:…”