Can I travel without my husband's permission?

There are two views with regards to travel. The first view is the majority of scholars say that it's not permissible for a female to travel without a mahram. And maybe your husband, remember that Allah has given him responsibility that he will be accountable for. The Prophet ﷺ said: All of you are responsible for your shepherd, for your sheep. Meaning that he's the shepherd, he's in charge of his flock, the ones who are responsible for him. And he will have to answer to Allah for that. So there are two views with regards to travelling without a mahram. The first view is the majority view, it's not allowed without a mahram. The second view which is nowadays given that the reason for the prohibition was a concern about security and safety. Nowadays that's not present particularly if you're travelling in groups or on airplanes and so on. That's also a problem valued view. So it could be that he's choosing the first view rather.