EPS Download Prescription By ID for Wales

Hi!
There is an interesting exception when one of our collegues is trying to download a prescription by id.

The flow steps are:

  1. Donwload Prescription By ID 1 - 200 OK
  2. Download Prescription By ID 2 - 400 Error with this exception Outcome
    {"resourceType":"OperationOutcome","issue":[{"severity":"error","code":"processing","diagnostics":"[element=\"value\"] Invalid attribute value \"\": Attribute value must not be empty (\"\")"}]}

So, some time ago we already had smth like that when Organization Parameter was empty or GroupIdentifier, but it is fixed now.
And it occures only for specific colleague using some work VPN and Network config.
Also, it is failing only for Wales Pharmacy NacsCode. There is no such issues for England Pharmacies.
In debug we could see that all the needed fields are ok and there no difference between Engalnd Pharmacy release request and Wales one. Also no difference between 1st and 2nd requests for Wales Pharmacy, but 1st one is always succeed, others are failing.
1st request - means, we restart the application and start making requests.
2nd request - is when we try donwload another prescription wihtout stopping/restarting the app.
Did you ever had smth like that?
Do you have any idea why it may happen in a such setting for Wales region?