How to solve JNA error "Only part of a ReadProcessMemory or WriteProcessMemory request was made"?

Question

I'm trying to write a little trainer in Java, but I'm stuck on ReadProcessMemory. I use JNA and JNA platform v5.6.0 in my project. When I try to readProcessMemory this way

Psapi.MODULEINFO moduleinfo = process.getModuleInfo("ac_client");
long base_address = Pointer.nativeValue(moduleinfo.lpBaseOfDll);

int player = process.readInt32(base_address + player_ptr);

I have this error:

Only part of a ReadProcessMemory or WriteProcessMemory request was made.

The base address and the player_ptr are the right one. All the examples of ReadProcessMemory that I saw on internet are not with a pointer as a parameter for the memory address.

Here is my full class.

   private final HANDLE process;

    private BProcess(HANDLE process) {
        this.process = process;
    }

    public static BProcess open(String name) {
        WinDef.HWND window = User32.INSTANCE.FindWindow(null, name);

        IntByReference i_ref = new IntByReference();

        User32.INSTANCE.GetWindowThreadProcessId(window, i_ref);

        HANDLE process = Kernel32.INSTANCE.OpenProcess(WinNT.PROCESS_VM_READ | WinNT.PROCESS_VM_OPERATION | WinNT.PROCESS_VM_WRITE, false, i_ref.getValue());

        return new BProcess(process);
    }

    public int readInt32(long address) {
        Pointer buffer = new Memory(4);
        Pointer p_address = new Memory(8);

        p_address.setLong(0, address);

        IntByReference iref = new IntByReference();

        boolean b = Kernel32.INSTANCE.ReadProcessMemory(this.process, p_address, buffer, 4, iref);

        if (!b) {
            System.out.println(p_address.getLong(0));
            throw new Win32Exception(Native.getLastError());
        }

        return ByteBuffer.wrap(buffer.getByteArray(0, 4)).get();
    }

    public Psapi.MODULEINFO getModuleInfo(String name) {
        WinDef.HMODULE[] hmodules = new WinDef.HMODULE[400];
        IntByReference i_ref = new IntByReference();
        boolean b = Psapi.INSTANCE.EnumProcessModules(this.process, hmodules, hmodules.length, i_ref);

        if (!b) {
            throw new Win32Exception(Native.getLastError());
        }

        WinDef.HMODULE module = null;
        int i = 0;

        while ((module = hmodules[i]) != null) {

            char[] c = new char[500];
            Psapi.INSTANCE.GetModuleFileNameExW(this.process, module, c, 500);
            System.out.println(new String(c));

            String moduleName = new String(c);

            if (moduleName.contains(name)) {
                break;
            }
            i++;
        }

        if (module == null) {
            throw new NoSuchElementException(name);
        }

        Psapi.MODULEINFO moduleinfo = new Psapi.MODULEINFO();

        Psapi.INSTANCE.GetModuleInformation(this.process, module, moduleinfo, moduleinfo.size());

        return moduleinfo;
    }

    public void close() {
        Kernel32.INSTANCE.CloseHandle(this.process);
    }