A current carrying circular loop of radius R is placed in the x-y plane with centre at the origin. Half of the loop with x>0 is now bent so that it now lies in the y-z plane.

For a circular loop of radius R, carrying current I in x-y plane, the magnetic moment M = I x $\mathrm{\pi }$$R^2$.
It acts perpendicular to the loop along z-direction.
When half of the current loop is bent in y-z plane, then magnetic moment due to half current loop is x-y plane, M₁ = I $\mathrm{\pi }$$R^2$/2) acting along z-direction.
Magnetic moment due to half current loop in y-z plane, M₂ = I($\mathrm{\pi }$$\frac{R^2}{2}$) along x-direction.
Net magnetic moment due to entire bent current loop, 
$\begin{array}{l}{\mathrm{M}}_{\text{net }}=\sqrt{{\mathrm{M}}_1^2+{\mathrm{M}}_2^2}\\ =\sqrt{2}\frac{{\mathrm{I\pi R}}^2}{2}\\ =\frac{\mathrm{M}}{\sqrt{2}}\end{array}$
Therefore, M_net < M or M diminishes.