Appointments+ strange signs in confirmation emails iPhone mail

Hi!

I have some troubles with Appointments+ confirmation mails opened in iPhone Mail app.

Its strange because with gmail or airmail i see it perfectly.

Characters problematics are: á é í ó ú and signs like ¡

Problems too with url displayed

I add a screenshot with airmail version and iphone version of the same message: http://note.io/1ihhHDi

Url: coachclouder.com/cita

Can someone help my with this little CSS problem in the same page:

https://premium.wpmudev.org/forums/topic/help-with-a-little-css-problem-with-appointments#post-581857

Thanks to all