Couldn't find a square in an image using open cv python - opencv

Question

Square detection in an image using cv2.rectangle()
image Using drawcontours(), I can see multiple points
Original image
I am able to detect two out of three squares.
The problem is that this is just a part of a very wide image, and only one square is undetectable. One big green box is missing and it is not detectable.
Can you help in square detection?
I have used the below code:
def getContours(img,imgContour):
contours, hierarchy = cv2.findContours(img, cv2.RETR_TREE, cv2.CHAIN_APPROX_NONE)
contours = sorted(contours, key = cv2.contourArea, reverse = True)
# image_number = 0
for cnt in contours:
area = cv2.contourArea(cnt)
# cv2.drawContours(imgContour, cnt, -1, (255, 0, 255), 7)
peri = cv2.arcLength(cnt, True)
approx = cv2.approxPolyDP(cnt, 0.02 * peri, True)
print(len(approx))
# if len(approx) == 4:
x , y , w, h = cv2.boundingRect(cnt)
ar = w/h
if ar >= 0.95 and ar <= 1.05:
cv2.rectangle(imgContour, (x , y ), (x + w , y + h ), (0, 255, 0), 5)
def auto_canny(image, sigma=0.33):
# compute the median of the single channel pixel intensities
v = np.median(image)
# apply automatic Canny edge detection using the computed median
lower = int(max(0, (1.0 - sigma) * v))
upper = int(min(255, (1.0 + sigma) * v))
edged = cv2.Canny(image, lower, upper)
# return the edged image
return edged
imagePath = "image3.jpg"
image = cv2.imread(imagePath)
imgContour = image.copy()
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
blurred = cv2.GaussianBlur(gray, (3, 3), 0)
auto = auto_canny(blurred)
getContours(auto,imgContour)