Awful spam in the last month

I’ve had to remove this plugin for 2 clients due to the sudden huge influx of spam messages (like 1 spam getting through a month, to 30 messages of smut spam in a day), and there is no ability to use a Recaptcha or anything. Very disappointing. Never had an issue til recently, so I assume something must have changed.
Would love to know if there is a fix or workaround. Or recommendations on a new plugin to use if this one isn’t getting fixed.