The ornamental design for a paymentmachine, as shown and described.
FIG. 1 is a front view showing an embodiment of the payment machine;
FIG. 2 is a rear view thereof;
FIG. 3 is a left-side view thereof;
FIG. 4 is a right-side view thereof;
FIG. 5 is a top view thereof;
FIG. 6 is a bottom view thereof;
FIG. 7 is a front-right perspective view thereof; and,
FIG. 8 is a rear-left perspective view thereof.
The broken lines in the drawings depict parts of the payment machine that form no part of the claim. Any shading and cross-hatching are not features of the design but are utilized to illustrate the surface contours of the payment machine in the drawings.