Help: get "partial write: max-values-per-tag limit exceeded (500002/500000)" but "SHOW TAG VALUES CARDINALITY" is lower more

Telegraf
1

when i insert into influxdb, get the following error:
2020-08-13 19:42:13,209 [ForkProcess-1:68162] [MainThread:140048873797440] [kafka2Influx.py:123] [kafka2Influx:writeInflux] [CRITICAL] - InfluxDBClientError: 400: {“error”:“partial write: max-values-per-tag limit exceeded (500002/500000): measurement="reversepry_request" tag="url" value="/files/DIR8596/8596409.txt" dropped=2”}

i checked the status of influxdb:

SHOW TAG VALUES exact CARDINALITY WITH KEY = “url”;
name: reversepry_request
count

102440

I am confusing when got the different values