Processflow Line Level approval error in RSS

Hello,

We're setting up Line Level approvals for Processflow using RSS.

We've got the Services and processes set up and enabled to use the 3 line level approval services using Pflow administrator.

We've got IC01, RQ04 flags to use Line level approvals.

In RSS, when ordering and then proceeding to checkout, all users are getting the error within RSS:

"Processflow Line Level approval not enabled"

I've triple-checked all of the set up with the Processflow set up and RSS set up but still I don't know where else to enable line level approval. I've looked in KB and also using GSC/LIS but still no luck.

Any ideas?

Thanks,

Roger