Restrict User Entry values for OVS F4 - Select Options

Hello Experts,

I have implemented Select Options Component and for one of the field, am using OVS.

Every thing is working fine, but the problem is, I need to restrict the user by entering the values manually into the field without selecting it from F4.

I have checked so many threads, but not able to get the right one.

Please help on with your valuable suggestions of how can I restrict the user to manually enter values directly into the field without selecting from F4 for an OVS of Select Options.

BR,

RAM.