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Ada input format issue

I'm new to Ada and not sure how to fix this code. It appears it is about format issue,ย but don't know what is causing this. I am trying to read two files called a.txt and b.txt then compute the inverse of it. Sorry again am just stuck.

Here is the input files

A.txt

2 -2 4 -2 2 0 
1 0 4 -3 0 0
1 1 1 1 1 1 
1 0 0 -1 0 0
3 0 0 -3 0 2
1 0 0 0 -2 4

B.txt

13
18
51
82
32
12

here is my code

with Ada.Text_IO, Ada.Float_Text_IO, Ada.Integer_Text_IO;
use Ada.Text_IO, Ada.Float_Text_IO, Ada.Integer_Text_IO;

procedure Matrix_Inverse is

   type Matrix is array (1 .. 6, 1 .. 6) of Float;
   type Vector is array (1 .. 6) of Float;
   
   function Get_Matrix_From_File(Filename : String) return Matrix is
      A : Matrix := (others => (others => 0.0));
      File : File_Type;
      Line : String (1 .. 20);
      Last : Natural;
   begin
      Open (File, In_File, Filename);
      for I in A'Range(1) loop
         Get_Line (File, Line, Last);
         for J in A'Range(2) loop
            A (I, J) := Float'Value (Line (1 .. Last));
            Get (File, Line);
            Get_Line (File, Line, Last);
         end loop;
         A (I, 6) := Float'Value (Line (1 .. Last));
      end loop;
      Close (File);
      return A;
   end Get_Matrix_From_File;
   
   function Get_Vector_From_File(Filename : String) return Vector is
      B : Vector := (others => 0.0);
      File : File_Type;
   begin
      Open (File, In_File, Filename);
      for I in B'Range loop
         Get (File, B (I));
      end loop;
      Close (File);
      return B;
   end Get_Vector_From_File;
   
   procedure Print_Matrix(A : Matrix) is
   begin
      for I in A'Range(1) loop
         for J in A'Range(2) loop
            Put (A (I, J), 6, 2);
            Put (" ");
         end loop;
         New_Line;
      end loop;
   end Print_Matrix;
   
   function Inverse(A : Matrix) return Matrix is
      Inv : Matrix := (others => (others => 0.0));
      Identity : Matrix := (others => (others => 0.0));
   begin
      for I in Identity'Range(1) loop
         Identity (I, I) := 1.0;
      end loop;
      
      for I in A'Range(1) loop
         if A (I, I) = 0.0 then
            for J in I + 1 .. A'Range(1)'Last loop
               if A (J, I) /= 0.0 then
                  for K in A'Range(2) loop
                     A (I, K) := A (I, K) + A (J, K);
                     Identity (I, K) := Identity (I, K) + Identity (J, K);
                  end loop;
                  exit;
               end if;
            end loop;
         end if;
    for J in A'Range(1) loop
      if J /= I then
          declare
            Factor : constant Float := A (J, I) / A (I, I);
          begin
            for K in A'Range(2) loop
                A (J, K) := A (J, K) - Factor * A (I, K);
                Identity (J, K) := Identity (J, K) - Factor * Identity (I, K);
            end loop;
          end;
      end if;
    end loop;

    for I in A'Range(1) loop
      declare
          Diagonal : constant Float := A (I, I);
      begin
          for J in A'Range(2) loop
            Identity (I, J) := Identity (I, J) / Diagonal;
          end loop;
      end;
    end loop;

      return Identity;
    end Inverse;

  function Solve(A : Matrix; B : Vector) return Vector is
    Inv_A : Matrix := Inverse(A);
    Result : Vector := (others => 0.0);
  begin
    for I in Result'Range loop
        for J in Result'Range loop
          Result (I) := Result (I) + Inv_A (I, J) * B (J);
        end loop;
    end loop;
    return Result;
  end Solve;

  A : Matrix := Get_Matrix_From_File("a.txt");
  B : Vector := Get_Vector_From_File("b.txt");

  Solution : Vector := Solve(A, B);

  begin
    Put_Line("Solution:");
    for I in Solution'Range loop
        Put(Solution(I), 6, 2);
        Put(" ");
    end loop;
    New_Line;
end Matrix_Inverse;
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