You can’t expect people to know who you are after letting your communications with them lapse for several months or years. If you connect people and then, don’t check in on them frequently, you will need to re-establish who you are and how you helped, even how did we meet. People in your network should not have to ask who you are when you are reaching out. In fact, they should go out of their way to make sure they are available to receive your communication.
If you can’t find the time to call your connections, you can reach out via private messages or email. While calling or meeting direct are the preferred means to communicate, these other methods are better than not reaching out at all. The key is to keep your name on their radar.
Nurture your connections for the future.