Return all of the ground actions possible instead of failing for just one

When I use solver API, the following case happens. I didn't have any action named ```reach-goal```. Here is the return json:
```
{
"status": "ok",
"result": {
"parse_status": "ok",
"length": 7,
"plan": [
"(move a1 b1)",
"(move b1 b2)",
"(move b2 b3)",
"(move b3 a3)",
"(move a3 a4)",
"(move a4 a5)",
"(reach-goal)"
],
"error": "'reach-goal'",
"output": "\n\ntask contains conditional effects. turning off state domination.\n\n --- OK.\n Match tree built with 19 nodes.\n\nPDDL problem description loaded: \n\tDomain: PACMAN_MID\n\tProblem: PACMAN-LEVEL-1\n\t#Actions: 19\n\t#Fluents: 20\nLandmarks found: 1\nStarting search with IW (time budget is 60 secs)...\nrel_plan size: 6\n#RP_fluents 10\nCaption\n{#goals, #UNnachieved, #Achieved} -> IW(max_w)\n\n{1/1/0}:IW(1) -> [2][3][4][5][6][7][8]rel_plan size: 0\n#RP_fluents 0Plan found with cost: 7\nTotal time: -1.07288e-09\nNodes generated during search: 42\nNodes expanded during search: 34\nIW search completed\n",
"type": "simple",
"planPath": "/tmp/solver_planning_domains_tmp_4CKg1JPQfz3GC/plan",
"logPath": "/tmp/solver_planning_domains_tmp_4CKg1JPQfz3GC/log"
}
}
```
Could you please help me out on figure out how could this happened?