Pendulum check

Hi Attached below is my staad model for a simple pendulum.

I am having these warnings:
***WARNING - INSTABILITY AT JOINT 2 DIRECTION = FY

Can anyone check my model, please?

STAAD PLANE
START JOB INFORMATION
ENGINEER DATE 10-Aug-23
END JOB INFORMATION
INPUT WIDTH 79
UNIT METER KN
JOINT COORDINATES
1 0 0 0; 2 0 0.9 0;
MEMBER INCIDENCES
1 2 1;
DEFINE MATERIAL START
ISOTROPIC STEEL
E 2.05e+008
POISSON 0.3
DENSITY 76.8195
ALPHA 1.2e-005
DAMP 0.03
TYPE STEEL
STRENGTH FY 253200 FU 407800 RY 1.5 RT 1.2
END DEFINE MATERIAL
MEMBER PROPERTY AMERICAN
1 PRIS YD 0.01
CONSTANTS
MATERIAL STEEL ALL
MEMBER TENSION
1
SUPPORTS
2 FIXED BUT FY FZ MX
LOAD 1 LOADTYPE Dead TITLE G
SELFWEIGHT Y -1
JOINT LOAD
1 FY -0.245
LOAD 2 LOADTYPE Seismic TITLE EX
JOINT LOAD
1 FX 0.1
LOAD 3 LOADTYPE Seismic TITLE EY
JOINT LOAD
1 FY -0.295
LOAD COMB 6 EY+EX
2 1.0 3 1.0
PERFORM ANALYSIS
FINISH