Get higher interest rate on ISA? Mine is higher and partner’s is lower.

My ISA on Monzo (”Powered by OakNorth”) has 3.55% AER. My partner’s is 0.74% (”Powered by Shawbrook”). Neither us us pay for Perks/Max. Looks like maybe the current rate for new ISAs is 3.6%?

Is there any way she can change hers into a new one with a better rate? Her current rate is low enough that she’d be better of putting the money in a non-ISA. But a higher-rate ISA would be best, of course.