v-select not retaining the correct value

Hi people, I need help with this please I have a v-select element as shown in the image, the values for the v-select are "Days" and "Months" which are contained into the array termFormatList. The issue here is that when I change the select from Months to Days the value is updated as it should work, but when I try to change from Days to Months the updated value is not being shown, as soon as I click in my button to save the value it returns to "Days" instead of keeping the value of "Months". When checking for the values in console and tracking the flow to my backend it shows that the value of "Months" is being handled, it is only a front issue, yet I have not been able to solve it.