It looks like each segment is 7 lines long, so you can read the data into a list, the use zip and iter to break it into a list of lists, each list being 7 elements long. Then you can write each one of those to a file.
If you are curious how zip(iter) works check out the details here
with open('users.txt') as f:
data = f.readlines()
for c, file in enumerate(zip(*[iter(data)]*7)):
with open(f'file_{c}.txt', 'w') as f:
f.writelines(file)
Or if you want the files names by the users
with open('users.txt') as f:
data = f.readlines()
for file in zip(*[iter(data)]*7):
name = file[0].split('=')[-1].split(';')[0].strip()
print(name)
with open(f'file_{name}.txt', 'w') as f:
f.writelines(file)