Cannot save dataset after removing join - column_name_mismatch

Hello all,
I duplicated a dataset, in order to create a new one with a couple of joined table. The duplicated dataset already had joined tables existing, which I needed to remove.
Unfortunately, I cannot remove one of the joined table, and save my new dataset for the new join. When saving, it says “Unable to save and publish dataset”, with the error message COLUMN_NAME_MISMATCH below, which says “Location Country Code (CPH)” is not in the column list of the dataset. But that field shouldn’t be there, as it was part of the old joined table which I needed to remove…
So, I’m a bit confused with how to proceed, as there shouldn’t be any column name mismatch, with only the left table remaining for the new join. There are no calculated fields in the dataset which are using any of those fields.
Would be great to get some guidance on this, as I’m stuck with a dataset I cannot use for the new join.
For information, the left dataset I need to keep was built by another BIE who onboarded the fields without any issues (from a datanet job). The original one prior to duplicating is working pretty well with the joined tables.

Many thanks!

I was able to solve the issue. Here are the steps if it can help someone with a similar problem:
-there was a column mismatch, but the issue was about the column level security (CLS) applied on the duplicated dataset. I first had to revert to the old join, as the problematic column wasn’t part of the dataset anymore (hence the column mismatch). The revert can be done in the dataset properties.
-Then removed all CLS from the duplicated dataset
-Then removed all the joins, and applied the new ones.