I’m using iv_robust to estimate the effect of voting (E3014_PR_1) on affective polarisation using voting eligibility as instrument – how do I add gender as an interaction term for voting?

I tried in many different ways but it always gives me a warning message:

“Warning in iv_robust(affpol_un ~ E3014_PR_1 * gender + education + E1008 | :
More regressors than instruments”

iv_robust(
    affpol_un ~ E3014_PR_1 * gender + education + E1008 |
    voting_eligibility + gender + education + E1008,   
    data = df,
    se_type = 'stata'
)

# Or

iv_robust(formula = affpol_un ~ E3014_PR_1 * gender + education + 
    E1008 | voting_eligibility + gender + education + E1008, 
    data = df)