[R] lmer model with continuos non normal response variable, transformation needed?

Hi. I want to do an lmer model but have doubts of what family I should use. My response variable was originally a proportion, however I standarized it for each year of data collection (20 in total). After standarizing it I checked for normality with the Kolmogorov-Smirnov test, and it turns out

[R] warning message for lmer model with poisson family

Hello, I'm trying to run an lmer model with family poisson but receive the following warning message: model-lmer(count~tem+dat+alt+year+tem:dat+tem:alt+tem:year+dat:alt+dat:year+alt:year+(1|id),family=poisson) Error in objective(.par, ...) : Leading minor of order 2 in downdated X'X is not