Subscribers can't browse internet when on 4G only

Dear Experts
I have a strange case happened with us: that one site (radio site) area has All its subscribers (Data SIMs only) can’t browse internet on 4G only (they can access 4G but no internet or very very slow almost 0 MB).
The weirdness come from the fact that all SIM cards which support voice and data can browse on 4G normally. Only Data SIMs have this issue.
So what possible scenario could have happened (is it core side VAS side or where possibly would be the problem?
Could it be related to RRC reconfigurations bearers?

Likely they have wrong HSS profile.
Audit parameters in HSS.

If only one radio node, check TAC, enodeB ID (ECI).

But this was not the case from long time ago, only few days back Dear

Not only one dear, many nodes. :frowning:
I suspect SRAN update issue maybe…

Dear @ran_core_consultant, can you elaborate?
The strange thing is the same SIM are working when they are served by another non problematic sites.
Only under these specific sites they loose internet access when connected to 4G.

Right. I thought this was network wide issue, which is why suggested to check HSS profiles.
If its only specific sites then I would check:

  1. Compare bearer setup parameters (Max bit rate, etc) on good site and bad site.
  2. Check if the UEs have special priority (SPID to go on to specific layer like 5 MHz due to congestion) on these sites.

It is strange really, I will check bearer setup ISA and get back to you but for the second point there are no HO to other layers, same cell exactly.