Mann-Whitney Non-parametric tests

#1
Hi,

I need to perform non-parametric tests:Mann-Whitney. But, I've read that to perform this test, I need to assure the equality of variances (levene test) and the equality of the distribution (boxplots, etc)...but, I couldn't assure this assumptions...this mean I cant use this non-parametric test? In such case, what can I do?
Thanks