Sort all tokens by username and count:

SELECT authCache.USERNAME, person.DISPLAYNAME, COUNT(*) AS tokens
  FROM HOMEPAGE.OH2P_CACHE AS authCache
  INNER JOIN HOMEPAGE.LOGINNAME AS loginName ON (loginName.LOGINNAME = authCache.USERNAME)
  INNER JOIN HOMEPAGE.PERSON AS person on(person.PERSON_ID = loginName.PERSON_ID)
  GROUP BY authCache.USERNAME, person.DISPLAYNAME
  ORDER BY COUNT(*) DESC

Show token count for single user

SELECT count(*) FROM HOMEPAGE.OH2P_CACHE WHERE  clientid = 'conn-rte' AND USERNAME = 'username'

Delete tokens for single user:

DELETE FROM HOMEPAGE.OH2P_CACHE WHERE  clientid = 'conn-rte' AND USERNAME = 'username'

Solution:

Edit /opt/IBM/WebSphere/AppServer/profiles/Dmgr01/config/cells/<cellname>/oauth20/connectionsProvider.xml and set

<!-- optional limit for the number of tokens a user/client/provider combination can be issued -->
<parameter name="oauth20.token.userClientTokenLimit" type="ws" customizable="true">
    <value>250</value>
</parameter>

this value to 500!

news-config.xml:

<!-- Each month a scheduled task runs to cleanup the oauth 2P Cache table in Homepage. -->
    <task description="Job to clean up the OAuth 2P Cache" enabled="true" interval="0 0 6 ? * SUN" mbeanMethodName="" name="OAuth2PCacheCleanup" scope=    "cluster" serverName="unsupported" startby="" targetName="ScheduledTaskService" type="internal">
</task>