Try a yoga mat that is good for hot yoga specifically! I have Lululemon The Reversible and it's great - one side for regular yoga, and the other side for when you need more grip (it's perfect for hot yoga, or someone who doesn't want to slip). A little pricey but I've had mine for 5+ years and have zero complaints - it's still holding up really well.
I use the Manduka PROLite and I love it. I've had it for 7 years (they have a 10-year warranty), I use it every day and have never tired of it. It's a bit thicker (5mm) which is more comfortable for knees. I highly recommend.
(I also have a Lifeform which is also great. The size is a bit larger in both width and length than the Manduka and it has lines on the mat which is nice for alignment, but I still prefer my beloved Manduka.)