Linking two aggregated tables

Hello,

I have two tables aggregated from two sources each: table 1 and table 2

In table 1 i have columns: unit code (unique and not repeating), number of subscribers 1

In table 2 i have columns: unit code (can repeat for some rows), number of subscribers 2, chanel health (has three possible values: good, weak, excellent)

I want to create a merge table which will link these two tables based on unit code and give as a result a table containing the following columns: Unit code, number of subscribers 1, number of subscribers 2, chanel health

Using DAX expression in Power BI, I tried this: Merged_Table = NATURALINNERJOIN(table 1, table 2) but it says: No common join columns detected.  although unit code is a commun column......

Can you help me please I am blocked

Thanks