Please refer below link for known limitation in ME3600/Me3800:SVI Limitations:https://www.cisco.com/c/en/us/td/docs/switches/metro/me3600x_3800x/software/release/15-5_1_S/configuration/guide/3800x3600xscg/swmpls.htmlSupported and Unsupported configur...
We investigated this with TAC some time ago, latest release your config will work is 15.5.3.S5. All later releases reqest you to use "no switchport" on uplink ports facing to core. No ospf and mpls on int vlans. This confirmed feature, as Cisco sayin...