Estava usando os links do heroku normalmente quando começou a voltar 500 (Internal Server Error).
Erro:
Whitelabel Error Page This application has no explicit mapping for /error, so you are seeing this as a fallback.
Fri Feb 01 01:40:41 UTC 2019 There was an unexpected error (type=Internal Server Error, status=500). Could not open JPA EntityManager for transaction; nested exception is org.hibernate.exception.SQLGrammarException: Could not open connection
