How to add these two matrices

Please find the problem and resolve it. I am not able to add the two matrices.

import random
m1 = int(input("Enter total number of rows in the first matrix\n"))
n1 = int(input("Enter total number of columns in the first matrix\n"))
a  = [[random.random() for j in range(n1)]for i in range(m1)]

print("Enter the values in the first matrix one by one")
for i in range(m1):
    for j in range(n1):
        a[i][j] = input()

m2 = int(input("Enter total number of rows in the second matrix\n"))
n2 = int(input("Enter total number of columns in the second matrix\n"))
b  = [[random.random() for j in range(n2)]for i in range(m2)]

if (m1==m2 and n1==n2):

    print("Enter the values in the second matrix one by one")        

    for i in range(m2):
        for j in range(n2):
            b[i][j] = input()

    print("The first matrix is")

    for i in range(m1):
        for j in range(n1):
            print(a[i][j], end= "\t")
        print()

    print("The second matrix is")

    for i in range(m1):
        for j in range(n1):
            print(b[i][j], end= "\t")
        print()
    c = [[random.random()for j in range(n1)]for i in range(m1)]
    print("The sum  of the matrix is") 

    for i in range(m1):
        for j in range(n1):
            c[i][j] = a[i][j] + b[i][j]

    for i in range(m1):`enter code here`
        for j in range(n1):
            print(c[i][j], end= "\t")
        print()

I have used all the ways given on other posts like using c[i][j] = [x+y for x,y in zip(a,b)] etc. but it always give the same output like if i have the matrix as [1 2] and [2 3] then the sum c will be [12 23] while it should have been c = [3 5]

I want to thank in advanced and want to tell you that i am a new computer science student, just going through the basics. So , please help.