Mixture model problem

I have a data set which is assumed to be the mixture of weibull and uniform distribution. The data point are numbers from 0 to 2 and the model is specified as this:

The histogram indicates the distribution is will fitted by the mixture model. However, the output model weight of uniform distribution is very low (3%). The result did not change much even though I cut off the tail of the mixture distribution from 5% to 25%.

I was wondering if it is the problem of my code or it is what the data actually are.

Many thanks.