Observium alert email empty

Hi Team,

We're faicing problem toward alert checker message/email notification. I cant figure it out if its after latest update or in general. Haven't changed alert checker for about 6 months and everything was running smoothly and good. Few weeks ago i have received first empty email, it looks like this:

I thought it maybe be some generic glitch for one device, but no, now all printer toner alerts are comming empty.

Hope for some recommendations.

If more info necessary, please let me know.

Thanks, Ivo.