"\received letter about eye screening, ..."

What I liked

\received letter about eye screening, given phone number to contact. Rang 12 times between 09.00 to 09.30 on 15 March only to receive answerphone message saying opening hours from 9am. Well it was after 9am and it cost me money but no responses. If they are supposed to answer calls from 9am why don't they. Or at least switch over to relevant message. Costly experience and still no response by 09.38 off to work cant wait any longer. Yet if I dont turn up to appointment its my fault - all I need to do is change appointment as now cant get time off due to sickness Frustrated and annoyed,

What could be improved

answering the phone and putting in relevant voice message

Anything else?

taking responsibility rang other numbers to no avail.