system.runtime.interopservices.sehexception exception occur with random scenario

we have .net windows application which is running on surface by client.application sometime crashes and every time scenario is different but in event logs exception is same system.runtime.interopservices.sehexception was unhandled. i cannot reproduce this issue. here is the stack trace:

Exception Info: System.Runtime.InteropServices.SEHException
   at SpectrumNZ.GUI.Modules.frmMainShell.Dispose(Boolean)
   at System.ComponentModel.Component.Finalize()

and here is event logs:

Faulting application name: SmartClient.exe, version: 0.0.0.0, time stamp: 0x5bb5f8a9
Faulting module name: clr.dll, version: 4.7.3130.0, time stamp: 0x5b175f1a
Exception code: 0xc0000006
Fault offset: 0x0007ca5b
Faulting process id: 0x1cac
Faulting application start time: 0x01d47c695f8665dc
Faulting application path: {path}\SmartClient.exe
Faulting module path: C:\Windows\Microsoft.NET\Framework\v4.0.30319\clr.dll
Report Id: 42f6b2d5-0936-4033-a6eb-edff18e8d7fa
Faulting package full name: 
Faulting package-relative application ID:

cannot understand what is the issue behind. after doing some search i have found that it might be network issue but i'm not sure. i have update question with code where occurs

protected override void Dispose(bool disposing)
        {
            if (disposing )
            {
                FlushMemory();
                //--------------------------------------
                if (components != null)
                {
                    components.Dispose();
                }               

            }
            base.Dispose(disposing);
        }



[System.Runtime.InteropServices.DllImport("kernel32.dll", EntryPoint = "SetProcessWorkingSetSize", ExactSpelling = true, CharSet = System.Runtime.InteropServices.CharSet.Ansi, SetLastError = true)]
        private static extern int SetProcessWorkingSetSize(IntPtr process, int minimumWorkingSetSize, int maximumWorkingSetSize);
        public static void FlushMemory()
        {
            GC.Collect();
            GC.WaitForPendingFinalizers();
            if (Environment.OSVersion.Platform == PlatformID.Win32NT)
            {
                SetProcessWorkingSetSize(System.Diagnostics.Process.GetCurrentProcess().Handle, -1, -1);
            }
        }

Please help me to find the cause of this exception. Thanks