This happens when the system with SID for a given installation number is upgraded. The earlier entry has a different product version as apart the new one and hence a duplicate entry is created. What you have to do is
1. Delete both SIDS in SMSY
2. delete all entries for both systems in LMDB
3. Delete both entries in SLD manually
4. Now push from rz70.
Everything will ill be alright after you do this.
interval of job from system to sld - 720 mins std.
job from sld to LMDB - 10 mins
job from LMDB to SMSY - 10 mins
its important you check the jobs before you start the manual cleanup else your deletion will get replaced before you finish all 4 steps