I have a regular who describes himself as blind but has partial sight in one eye and manages amazingly well and his hearing is amazing. It sometimes feels like he hears things before the sound is even there
Well being blind or deaf isn't like flicking a on/off switch - like Mirror said, not many people have absolutely no vision at all (even if it's just telling light from dark) and not that people are so completely and profoundly deaf that they can't manage the phone at all even with hearing aids or in their 'better' ear (like I do, although I can only answer indoors in a quiet room and can't hear well enough to take calls outside or in a public place. Oh, and my eyesight is shit too
).
The 'I'm deaf and can't call, can I book by text?' punters have been around as long as text messaging has and the majority are address collectors who disappear as soon as they get it. There will be some who are genuine and whilst I can't accommodate them at my flat because of the difficulty directing them, I have no problem at all seeing somebody who can't hear me (espclecially when I mostly can't hear them either). I'd go with what somebody else said and think of a 'Stop' signal but otherwise I'd just proceed as usual
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