Hi @Anonymous ,
Based on the formula that you provided, I think there is something wrong with it. This issue is related to the LookUp function in your Filter formula. The LookUp function could only return the first record which matches the specific criteria.
If you use the LookUp function to find related record in your Table2 based on the Country_Table1 value in your Table1, it could only return the following record for Chile:

whose email address is not yours, so the Chile country would not show up in your Gallery.
I have made a test on my side, please take a try with the following workaround:
Set the Items property of the Gallery to following:
Filter(
Table1;
Country_Table1 in Filter(Table2; 'E-Mail_Table2' = Lower(User().Email)).Country_Table2
)
Please consider take a try with above solution, then check if the issue is solved.
Best regards,