Add an empty (@) A record, with the value of 174.129.25.170
Add a 'www' CNAME, with the value of imxprs.herokuapp.com
(If there are previous A records in your DNS settings - make sure to delete them).
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A record - Host --> @ (empty) points to --> 174.129.25.170
CNAME - Host --> WWW points to --> imxprs.herokuapp.com
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