Taxiway Bug at Batumi

[Eutro]

When Taxiing around Batumi in the MiG-21, I found that the section of the taxiway on the south side of the runway is bugged. The MiG seems to sink slightly into the ground and barely moves, even in afterburner. I tried several times, and it happens each time. I also tried it with the F-86, and the same thing happens. Seems to occur only on the taxiway between the runway and the two buildings south of the runway. Attached is a track showing the issue in the MiG.

MiG-21 Batumi Taxi Bug.trk