It is not practical (indeed it is not possible) for any reasonably busy solicitor to notify all of his\her clients of pending holidays.
Of course, it would be normal to have some arrangements in place for consultation on emergency issues. With respect, unless there is some deadline for signing contracts (which does seem very unlikely in the present market) it does not seem that this case falls into the emergency category. In fact, this seems like something which can clearly keep until the solicitor's return.
There may be more to it than is contained in your post, but if this is the only gripe, then I think your service expectations may be a little unrealistic.