WebAPI connection exception Error Subset Found: Server error-00150-No response returned from the server

When writing a Colleague custom WebAPI, I encountered a connection error while executing a transaction:

[Ellucian.Data.Colleague.Exceptions.ColleagueTransactionException] = {"Error Subset Found: Server error-00150-No response returned from the server."}

I made sure my credential was correct and the connection was established before calling the transaction. After much debugging, I found out that the string that was passed to the transaction exceeded the size limit of a field in Colleague. I passed in a 15 character long string and tried to write it to a 10 character long field in Colleague through the transaction, and it resulted in a truncation error which ended the Colleague session. This also returned the error above. They do not look like they're related, so it was hard to track down. Make sure you check the size of the arguments of the transaction when you get these error.