今天可转债行情接口（cb_daily）返回的纯债价值（bond_value）数据全是空值

今天的可转债行情接口（cb_daily）返回的纯债价值（bond_value）数据全是空值。是否是因为每到月末数据更新不及时？还是有其他的问题？望尽快改进。

pro.cb_daily(start_date='20230731', end_date='20230731', fields='ts_code,trade_date,close,bond_value,cb_value')

index	ts_code	trade_date	close	bond_value	cb_value
0	128100.SZ	20230731	18.00	None	26.25
1	128114.SZ	20230731	86.40	None	86.60
2	113578.SH	20230731	89.74	None	86.88
3	127047.SZ	20230731	91.35	None	57.05
4	110072.SH	20230731	93.71	None	55.33
...	...	...	...	...	...
499	123031.SZ	20230731	382.99	None	296.71
500	123018.SZ	20230731	398.21	None	90.43
501	123013.SZ	20230731	438.50	None	138.63
502	128111.SZ	20230731	469.50	None	425.31
503	123029.SZ	20230731	1376.60	None	562.31

waditu / tushare