这个问题通常是由于在制作表格时，没有使用自定义样式而使用了文档样式。为了解决这个问题，可以使用以下代码示例在表格中应用自定义样式：

from docx.enum.table import WD_TABLE_ALIGNMENT
from docx.enum.text import WD_PARAGRAPH_ALIGNMENT
from docx.shared import Pt
from docx.oxml import OxmlElement
from docx.oxml.ns import qn

def set_row_style(row):
    for cell in row.cells:
        cell.vertical_alignment = WD_CELL_VERTICAL_ALIGNMENT.CENTER
        cell.paragraphs[0].alignment = WD_PARAGRAPH_ALIGNMENT.CENTER
        for paragraph in cell.paragraphs:
            for run in paragraph.runs:
                font = run.font
                font.size = Pt(9)
                font.name = 'Arial'

def set_col_widths(table, col_widths):
    total_width = sum(col_widths)
    for i, width in enumerate(col_widths):
        col = table.columns[i]
        col.width = Pt(width/total_width*sum(table._tbl.width))

def set_table_style(table):
    tbl = table._tbl  # get xml element in python-docx
    nsprefixes = dict([(k, v) for k, v in tbl.nsmap.items() if k])
    ns0 = nsprefixes.get('', 'w')  # get default namespace (w)

    # set table style to medium grid 1 accent 2
    tblStyle = OxmlElement('w:tblStyle')
    tblStyle.set(qn('w:val'), 'Table Grid')
    tblPr = tbl.find(qn('w:tblPr'))
    tblPr.append(tblStyle)

    # set table width
    tblW = tblPr.find(qn('w:tblW'))
    tblW.set(qn('w:w'), '5000')
    tblW.set(qn('w:type'), 'pct')

    # set vertical alignment of cells
    for cell in table._cells:
        tc = cell._tc
        tcPr = tc.get_or_add_tcPr()
        tcVAlign = OxmlElement('w:vAlign')
        tcVAlign