Why i call someone and it reaches voicemail. But they say i did not ring. What causes that and how to fix it . But sometimes it call good. They have not set anything to block my calls

There could be several reasons why your calls may sometimes go to voicemail without ringing on the recipient's end. Some possible causes include:

1. Network issues: This could be due to poor network coverage in the recipient's area, which may cause calls to go straight to voicemail without ringing.

2. Phone settings: The recipient may have their phone on do not disturb mode or may have customized settings to send certain calls directly to voicemail.

3. Phone signal: If the recipient's phone is out of range or has a weak signal, calls may go straight to voicemail.

4. Call forwarding: The recipient may have set up call forwarding to another number, which can result in calls going straight to voicemail without ringing.

To fix this issue, you can try the following steps:

1. Ask the recipient to check their phone settings, network connection, and call forwarding settings to ensure that there are no restrictions preventing your calls from ringing.

2. Ensure that your phone has a strong network connection before making the call.

3. If the issue persists, you can try contacting your service provider to check for any network or technical issues that may be causing the problem.

Overall, it may require both you and the recipient to troubleshoot and potentially make changes to settings or network connections in order to ensure that your calls go through successfully.