You may also be able to ask Republic Wireless to switch your underyling number to another one. (I believe every Republic Wireless phone has 2 numbers: your main number + and underlying number).
If your underlying number is changed, this may or may not help to reduce your spam calls.
I personally try for the most part to not answer a call that’s not in my contact list. Many times, I’ll let it go to my voicemail, and in my voicemail, I encourage people to text me because I’ll typically respond to texts faster. I figure if someone leaves me a personal voicemail and/or texts me, they’re less likely to be a spammer, and I save time from having to answer spam calls.