Cannot create a new tiff file with rasterio?

Question

So I am trying to create a new tiff file with rasterio and numpy and this is my code

#import rasterio
import rasterio
#import show from rasterio.plot
from rasterio.plot import show
#import numpy
import numpy
from affine import Affine

#read the tif file
dataset = rasterio.open('montreal_30m.tif')
#obtain information of dataset
dataset.transform
band = dataset.read(1)
rows = []
for i in range (0,len(band),3):
    cols = []
    for j in range (0,len(band[0]),3):
        cols.append(band[i,j])
    rows.append(cols)
newband = numpy.array(rows, dtype = numpy.float32)

xcellsize = dataset.transform[0]*3
ycellsize = dataset.transform[4]*3

newtransform = Affine(xcellsize, 0.0, -73.629102716,0.0, ycellsize, 45.548661929)

with rasterio.open(
    'montreal_90m.tif',
    'w', 
    driver = 'GTiff', 
    height = len(newband), 
    width = len(newband[0]), 
    count = 1, 
    dtype = numpy.float32, 
    crs = dataset.crs, 
    transform = newtransform
) as newraster:
    newraster.write(newband, 1)

and I get this error message

CPLE_OpenFailedError                      Traceback (most recent call last)
<ipython-input-69-aa86b394c59e> in <module>
     26     dtype = numpy.float32,
     27     crs = dataset.crs,
---> 28     transform = newtransform
     29 ) as newraster:
     30     newraster.write(newband, 1)

/opt/conda/envs/python/lib/python3.7/site-packages/rasterio/env.py in wrapper(*args, **kwds)
    421 
    422         with env_ctor(session=session):
--> 423             return f(*args, **kwds)
    424 
    425     return wrapper

/opt/conda/envs/python/lib/python3.7/site-packages/rasterio/__init__.py in open(fp, mode, driver, width, height, count, crs, transform, dtype, nodata, sharing, **kwargs)
    223                                               transform=transform,
    224                                               dtype=dtype, nodata=nodata,
--> 225                                               **kwargs)
    226         else:
    227             raise ValueError(

rasterio/_io.pyx in rasterio._io.DatasetWriterBase.__init__()

rasterio/_err.pyx in rasterio._err.exc_wrap_pointer()

CPLE_OpenFailedError: Attempt to create new tiff file 'montreal_90m.tif' failed: No such file or directory

It looks like there might be something off with the transform but I'm not sure what that could possibly be since everything looks good to me. It also says no such file or directory so there could be a directory problem? I'm not sure how that's possible though since I was able to use rasterio fine to open the original tiff file. Honestly at this point I'm just confused.