If removing required: true resolves the issue, it suggests that the value being passed to the component might sometimes be null when the component is first mounted. The required: true option enforces that the prop must be provided, and in this case, it was expecting a non-null value.
When you removed required: true, the prop becomes optional, and Vue no longer raises a warning if the prop is initially null.
If it’s acceptable for the value prop to be null when the component is mounted, you can keep the prop as optional. However, if you want to enforce that a non-null value must be provided, you might want to ensure that the initial value passed to v-model is not null.