aggregate the dataframe according to the multi-layer in the axis=1 does not work！

[CatNofishing]

Pandas version checks

• I have checked that this issue has not already been reported.

• I have confirmed this bug exists on the latest version of pandas.

• I have confirmed this bug exists on the main branch of pandas.

Reproducible Example

import pandas as pd
import numpy as np

df=pd.DataFrame(np.random.rand(6,6))
df.columns=pd.MultiIndex.from_product([['b','c'],[1,2,3]])
df.groupby(level=0,axis=1).agg(['mean','max'])

Issue Description

I tried to aggregate the dataframe according to the multi-layer index in the axis = 1 direction, but it failed.

Expected Behavior

I expect result is

Installed Versions

INSTALLED VERSIONS

commit : db08276
python : 3.8.5.final.0
python-bits : 64
OS : Windows
OS-release : 10
Version : 10.0.18362
machine : AMD64
processor : Intel64 Family 6 Model 158 Stepping 10, GenuineIntel
byteorder : little
LC_ALL : None
LANG : None
LOCALE : Chinese (Simplified)_China.936

pandas : 1.1.3
numpy : 1.19.2
pytz : 2020.1
dateutil : 2.8.1
pip : 20.2.4
setuptools : 50.3.1.post20201107
Cython : 0.29.21
pytest : 6.1.1
hypothesis : None
sphinx : 3.2.1
blosc : None
feather : None
xlsxwriter : 1.3.7
lxml.etree : 4.6.1
html5lib : 1.1
pymysql : None
psycopg2 : None
jinja2 : 2.11.2
IPython : 7.30.1
pandas_datareader: None
bs4 : 4.9.3
bottleneck : 1.3.2
fsspec : 0.8.3
fastparquet : None
gcsfs : None
matplotlib : 3.3.2
numexpr : 2.7.1
odfpy : None
openpyxl : 3.0.5
pandas_gbq : None
pyarrow : 5.0.0
pytables : None
pyxlsb : None
s3fs : None
scipy : 1.7.1
sqlalchemy : 1.3.20
tables : 3.6.1
tabulate : None
xarray : None
xlrd : 1.2.0
xlwt : 1.3.0
numba : 0.51.2

[simonjayhawkins]

Thanks @CatNofishing for the report.

This gives a result in a pandas 1.3 onwards, but the result looks iffy, so this could be related to #46904

Closing this issue. Feel free to open a new issue using a newer release of pandas.

[rhshadrach]

Agreed - this is a duplicate of #46904. The result here is incorrect and this should raise instead.

[rhshadrach]

While the core issue is the same, it is possible to close #46904 without fixing this issue. I'm reopening to ensure it's closed appropriately.