UE is not able to attach to NR DSS cell.
What could be probable reason?
RACH is not initiated by UE though cell is radiating
Is cell eligible?
Are your IDLE mode parameters OK?
Yes, looks OK.
Check cell blacklisted for initial access.
You can check it in mib/sib1.
Is it reading mib sib?
Registration message there or not?
Check the ssb frequency position, there is rule either the delta with nr arfcn is mod2 or mod3 /mod6 depend on your band and scs. Assuming the DSS <3GHz scs 15khz so mod3=0.
If you put you ssb at lower or higher position, pls consider also some space for coresetzero.
It’s tested in Lab.
The moment LTE frequency is made different from NR frequency,the attach works.
I mean for DSS we keep LTE freq = NR freq and attach is failing.
This is a DSS test.
If frequencies are different UE attaches I mean.
DSS configuration must be wrong.
Check UE logs whether is acquiring all necesary information of NR (like MIB ,SIBs).
Is your test UE enabled and certified for DSS? Often the chipset is ready for DSS, but Carrier Settings within Android for DSS are disabled.
I assume your mobile is enabled for 5G, but DSS is disabled. This would explain why it attaches to 5G when frequencies are different and not when DSS (same freq.) is used.