Trying training tesseract 5.3.0, "Couldnt find a matching blob" for every zero in training data. Other characters okay

Question

Tesseract 5.3.0.20221222

When using command

tesseract.exe 1.png 1 box.train

I get the output

row xheight=25, but median xheight = 16
row xheight=25.5, but median xheight = 16
row xheight=25.5, but median xheight = 16
row xheight=25, but median xheight = 16
row xheight=25.5, but median xheight = 16
row xheight=25.5, but median xheight = 16
row xheight=13, but median xheight = 16
row xheight=12, but median xheight = 16
row xheight=10.4167, but median xheight = 16
row xheight=10.4167, but median xheight = 16
row xheight=12, but median xheight = 16
row xheight=10.4167, but median xheight = 16
row xheight=10.4167, but median xheight = 16
FAIL!
APPLY_BOXES: boxfile line 59/0 ((8,663),(26,695)): FAILURE! Couldn't find a matching blob
FAIL!
APPLY_BOXES: boxfile line 133/0 ((8,460),(26,492)): FAILURE! Couldn't find a matching blob
FAIL!
APPLY_BOXES: boxfile line 143/0 ((458,460),(476,492)): FAILURE! Couldn't find a matching blob
FAIL!
APPLY_BOXES: boxfile line 211/0 ((7,353),(17,372)): FAILURE! Couldn't find a matching blob
FAIL!
APPLY_BOXES: boxfile line 285/0 ((7,213),(17,232)): FAILURE! Couldn't find a matching blob
FAIL!
APPLY_BOXES: boxfile line 295/0 ((277,213),(287,232)): FAILURE! Couldn't find a matching blob
FAIL!
APPLY_BOXES: boxfile line 363/0 ((7,122),(15,137)): FAILURE! Couldn't find a matching blob
FAIL!
APPLY_BOXES: boxfile line 437/0 ((7,9),(15,24)): FAILURE! Couldn't find a matching blob
FAIL!
APPLY_BOXES: boxfile line 447/0 ((217,9),(225,24)): FAILURE! Couldn't find a matching blob
APPLY_BOXES:
   Boxes read from boxfile:     456
   Boxes failed resegmentation:       9
   Found 447 good blobs.
Generated training data for 51 words

The part of error saying "... boxfile line xxx/y", the xxx = the line number, and y = the character in question. It always fail for character "0".

I am using QT Box Editor v1.12rc1 to fix boxes generated by tesseract itself by command

tesseract.exe 1.png 1 batch.nochop makebox

Here is the screenshot of QT Box Editor showing the zeroes:

I tried copying the coordinates from the error ((217,9),(225,24)) and pasting it to QT Box Editor (theres a function directly for that), and it draws a box precisely around the zero in question correctly.

I thought maybe it has to do with the fact that the 0 is the first character on the line, so I added second 0-9 digits after the first one in three places. In total, there are 9 zeroes, with 6 of them at the left-most position, and 3 in the middle. All 9 in the picture are throwing error, and no other character is.

Honestly, I have no clue what is happening. Googling this error haven't helped me at all. When I continue with training, the character 0 obviously doesn't get trained and the character is then recognized as 8 most of the time.

What am I doing wrong?

I expect the blob of pixels representing zero to be recognized as such, as it works with every other character.