The spelling of the phrase "wert due to" may seem confusing at first glance, but it can be easily explained through phonetic transcription. "Wert" is an archaic form of "were," pronounced /wɜːr/. "Due" is pronounced /djuː/ and is used here as an adjective meaning "owed." Therefore, "wert due to" means "were owed to" in modern English. This construction is commonly found in older texts or formal writing, but may not be frequently used in everyday speech.