We have a similar issue with ISE 2.2 and Meraki MR latest release 25.9. It is more apparent with Android devices. When logging into the guest portal, ISE sends a CoA to the MR after a successful guest authentication. Sometimes we see ISE logs that the MR did not respond to the CoA request. Endpoints end up redirected recursively to the login page, then at some point it lets them in. It helps if they login then disable/re-enable their wifi. Seems like an MR issue since ISE is functioning properly. We upgraded from MR 24.x since it had a log of defects with CoA, but 25.9 did not fix the problem. Client event logs on MR do not show the problem but endpoint debugs in ISE show CoAs being sent to the MR with no apparent reply. Any ideas?
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