W-4 Witholdings

My wife and I file jointly.  We are both educators.  Combined income ~$155k.  2 children (13 & 15) Both of us claim 0 yet we still end up owing $4k the past 2 years, this just started to happen, up until then we received a refund.  We are not in a position financially to have additional money taken each pay check.   Any help is appreciated