I see this come up a lot so I'm just going to make a general post giving advice about what to do when someone is spamming rolls.
First of all you need to realise that by rolling, they're not really doing anything that threatening to you. If they want to roll, let them roll.
Rolling is only useful for punishing overcommitment. This is important so read that again.
What you want to do then is only use actions that don't leave you overly committed. If the move/action is laggy or keeps you in one spot for too long, just don't do it and they won't be able to get any reward out of rolling.
One thing rolling does obviously achieve is it adjusts the amount of space in between you both, so while making non-committed pokes at them, you want to make sure you adjust your spacing as they do, and if possible try to keep it so that they can't roll behind you. This can be done by either retreating or just jumping away.
The focus shouldn't be on punishing the rolling, rather it should be on maintaining the more neutral situation where they are essentially just wasting their time which will force them to use other options.
Having said that, you should be making your pokes with the intention of hitting them at the end of their roll. If they are literally spamming it, sometimes it helps to predict the next roll as this will give you more time to set up. Punishing rolls on reaction is difficult otherwise.
I will say this one more time for absolute clarity. Do not attempt to punish a roll with an attack that will leave you open to be punished yourself should you miss (unless you are amazing, in which case this entire post doesn't actually apply to you).