Thanks all for your help
The reason was silly but at the same time interesting. The view has multiple text joins with the column SPRAS. So HANA was renaming each SPRAS column with a prefix to make it unique. This was causing the problem with the language column I set as SPRAS.
Logically it could better if when the alias is set, the language dropdown also gets updated with the updated column name. But alls well that ends well ha?
Thanks all.