There is a limitation :
Standard ACL is not supported on FlexConnect AP mode
FlexConnect does not support IPv6 ACLs
https://www.cisco.com/c/en/us/td/docs/wireless/controller/9800/config-guide/b_wl_16_10_cg/flexconnect.html
Linking an ACL Policy to the Defined ACL (GUI)
Procedure
Step 1 | Choose . |
Step 2 | Click Add. |
Step 3 | In the General tab, enter the Name of the Flex Profile. The name can be ASCII characters from 32 to 126, without leading and trailing spaces. |
Step 4 | In the Policy ACL tab, click Add. |
Step 5 | Select the ACL from the ACL Name drop-down list and click Save. |
Step 6 | Click Apply to Device. |
Applying ACLs on FlexConnect
Procedure
Device# configure terminal
Device(config)# wireless profile flex Flex-profile-1
Device(config-wireless-flex-profile)# acl-policy ACL1
Device(config-wireless-flex-profile-acl)# exit
Device(config-wireless-flex-profile)# native-vlan-id 25
Device(config-wireless-flex-profile)# vlan-name VLAN0169
Device(config-wireless-flex-profile-vlan)# acl ACL1
Device(config-wireless-flex-profile-vlan)# vlan-id 169
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