First of all, why did HR do a telephone survey? Generally speaking, if you apply for a position that requires high confidentiality and integrity, or a management position, the company will be more cautious, and the responsible HR will indeed conduct background checks in person or through a third party.
Secondly, to what extent will HR telephone survey be done? It depends on the importance of the position you are applying for. If it is an ordinary or grass-roots management position, HR may make a telephone survey, but the survey will not be too detailed. Generally speaking, as long as the original unit does not deliberately slander you, it is basically no problem to make a symbolic phone call to the original unit. You know, usually telephone surveys are for recruitment assistants at the lowest level of HR, and some irresponsible people don't make such calls at all, because it's boring to call others and ignore them. If the position you are applying for is very important, people will not ask you to do a telephone survey at all, and they have already started to investigate you. Some even found out a few moles on your body through an outsourcing professional investigation company.
Then why did HR ask you to call to investigate this matter? In one case, he doesn't really want to investigate you. On the one hand, collect your information first to ensure that he is conscientious in this procedure and can remain active. On the other hand, he can also make further judgments from the contact information you left. Another situation is that a program really needs to be executed. For him, it is more about seeking inner peace.
The previous analysis is enough. Next, let's see what preparations should be made.
Do you want to leave the phone number of a close colleague, or the phone number of your direct supervisor or company HR? Here you mentioned that your previous performance was not very good. I didn't say anything bad, but I can analyze it. There are usually two reasons for poor performance. One is attitude, and I don't want to do it well. Second, the position is not suitable, I want to do well, but what I do is really not my specialty.
If you have an attitude problem, in this case, I suggest you leave the phone number of your close colleague and add a company switchboard. Some people may ask whether this is dishonest, but it is not. Anyone who wants to live can't completely expose his dark side and be slaughtered. Secondly, leaving the company switchboard shows that you have a clear conscience and are not afraid of investigation.
If you don't have a big holiday or have a conflict with your superiors because of your inappropriate position, I suggest you leave your superiors' phone number and add the company switchboard. Generally, in this case, the superior will not demote you. Of course, it's best to say hello to your superiors in advance. When you leave your superior phone number, you'd better leave your mobile phone number and landline number.
If you really communicate by telephone, you will usually ask standard questions something, such as how active you are at work. Is there any serious violation of discipline? How about honesty? Wait, it's been going on for five minutes. No one has the patience to answer the phone.
Generally speaking, first of all, you don't need to worry too much about this problem, but you can't just do it. You should give contact information selectively according to your previous performance.
I believe you will cross this hurdle and wish you a bright future again! :)