This error is occurring at the point you are trying to post the PR to Financials; to become a Purchase Order, or other type of Purchasing Transaction (depending on the configuration of the PR type in FinOps)
The error itself, is quite self explanatory. It essentially means that there is a forced Sub Ledger code for all transactions in all ledgers, in Financials. And so, without a Sub Ledger on the PR (or being provided in another way, the process for posting to Financials fails.
**First; check the settings in Financials to confirm whether Sub Ledger Codes are a compulsory field requirement.**
IF Sub Ledger codes are a compulsory field within the Financials application, check the Profiles in Financials for a Default Purchase Sub Ledger for the profile, the FinOps user posting the PR is in.
**It might be that the profile the user is assigned to does not have a default Sub Ledger set against it**
IF you do not require compulsory Sub Ledger codes, then change the settings in Financials to not require Sub Ledger codes as a compulsory entry field
IF you do require compulsory Sub Ledger codes to be enabled in your Financials application then you'll need a way to include the Sub Ledger codes on the PR.
To do this you'll need access to the FinOps Administrator application
Access to FinOps Administrator is currently not readily available to customers using FinOps, so the options to self serve are limited.