VMMDLL_Map_GetPool always false

[maoxian123]

DWORD iPoolTagEntry = 0, iPoolEntry = 0;
    PVMMDLL_MAP_POOL pPoolMap = NULL;
    PVMMDLL_MAP_POOLENTRY pPoolEntry;
    PVMMDLL_MAP_POOLENTRYTAG pPoolTag;
    bool result = VMMDLL_Map_GetPool(hVmm, &pPoolMap, VMMDLL_POOLMAP_FLAG_BIG);
    if (!result) {
        printf("FAIL:    VMMDLL_Map_GetPool.\n");
        return 1;
    }

why always return false,other func is right
the host win is 20h2 19042.928 and the software run at 1909