How to remove unclosed areas in OpenCV?

Question

Python

I have this picture, I processed it, but still I can’t get the contours of the letters because of the extra noise:
1) Source:

2) After processing


And here is the processing code, what needs to be added to correctly find the contours of the letters?

def detecting_and_extracting_letters(path,out_size=28):
    img = cv2.imread(path)
    img = cv2.cvtColor(img,cv2.COLOR_BGR2HSV)
   
    _, thresh = cv2.threshold(img,110,255, cv2.THRESH_BINARY)
    img_erode = cv2.erode(thresh, np.ones((3, 3), np.uint8), iterations=1)
    dilation = cv2.dilate(img_erode,np.ones((3, 3), np.uint8),iterations = 1)
    contours, hierarchy = cv2.findContours(dilation, cv2.RETR_TREE, cv2.CHAIN_APPROX_NONE)
    
    cv2.imshow("Input", img)
    cv2.imshow("Enlarged", dilation)
    cv2.waitKey(0)