What is the error and how to fix it, Python?

Question

Python

it is necessary that the python read 2 .txt files that are in the same directory (their names are txt A.txt, txt B.txt). when trying to read txt B.txt, an error pops up:

not enough values ​​to unpack (expected 2, got 1)

here is my code:

ares = {}

a = open('txt A.txt', 'r')
for line in a.readlines():
    name,score = line.split(",")
    ares[name] = int(score)

bres = {}

b = open('txt B.txt', 'r')
for line in b.readlines():
    name,score = line.split(",")
    bres[name] = int(score)

PS I already tried to change the variables in the b code itself, but still the error is still the same.