Logistic regression, after adding covariate interaction term, the key IV becomes insignificant (R studio)

I’m trying to understand why adding a covariate and an interaction term gives different results on the significance of the key IV from adding only the covariate. I have a categorical IV (2 levels), and a binary outcome (coded as 1 and 0). I also have a continuous covariate.

If I only add IV (i.e., condition) to the logistic regression model, the IV has a significant effect on DV:

glm(formula = DV ~ condition, family = "binomial", data = df)

(AIC: 307.38)

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If I add IV and the covariate to the logistic regression model, the IV still significant:

glm(formula = DV ~ condition + covariate, family = "binomial", data = df)

(AIC: 306.29)

enter image description here

But when I added IV, covariate and the interaction, the IV no longer significant but the covariate became significant:

glm(formula = DV ~ condition * covariate, family = "binomial", data = df)

(AIC: 306.48)

enter image description here

I’m so confused. It’s there any problem to add interaction to logistic regression, or it’s the fact that my IV doesn’t really have an effect on DV? I read a similar post here but I’m still confused.

Follow-up:
I tried to only include covariate in the model:

glm(formula = DV ~ covariate, family = "binomial", data = df)

(AIC: 308.69, not sure if this is relevant)

enter image description here

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