Merging entries fails in MultiTerm 2021

Hi,

Merging entries fails in MultiTerm 2021. Carrying out the command upon right-clicking on each of the three termbase entries and selecting "Merge entries" from the context menu does not do anything. We have used this step-by-step guidance  https://docs.sdl.com/791883/460278/sdl-multiterm-2017/zusammenfuhren-von-termini and this one http://producthelp.sdl.com/sdl_multiterm_2011/client_de/Working_with_Termbase_Entries/Editing_and_Deleting_Termbase_Entries/Merge_Terms.htm

I should add that "Edit" and "Save" are always greyed out in the termbase entry view/MultiTerm Editor view, in the case of each of the three Spanish to UK English entries for "Así mismo, ...".

Cheers,


Sebastian Witte