The ornamental design for a yogamatbag, as shown and described.
FIG. 1 is a front perspective view of a yoga mat bag;
FIG. 2 is a front elevation view of FIG. 1;
FIG. 3 is a rear elevation view of FIG. 1;
FIG. 4 is a left side elevation view of FIG. 1;
FIG. 5 is a right side elevation view of FIG. 1;
FIG. 6 is a top plan view of FIG. 1;
FIG. 7 is a bottom plan view of FIG. 1; and,
FIG. 8 is a front perspective view of the yoga mat bag, shown in an open configuration.
The broken line showing of is included for the purpose of illustrating and forms no part of the claimed design. The dash-dot broken lines on FIG. 8 represents the boundary and forms no part of the claimed design.