sending massage error won't sent shows an error

Judging from the icons shown in the sidebar of your screenshot, you are using Teams with a personal account (aka. Teams Free). I guess that you are signed in to Teams with Microsoft 365 Personal, Family or Premium email address.

There is no information available on what Teams account is your contact on. They might use Teams Business account, and they might not be able to receive messages from your Personal account. It is also possible that they have not yet accepted your contact invitation.

In any case, their connection status shown in your original screenshot is Offline (not connected on Teams). It is not possible to make calls to a user who is not connected to Teams.

I noticed that you’ve been using both English and Spanish in your previous messages. Please let me know which language you prefer so I can support you more conveniently and accurately.

Hi @Alexandra Segovia, 

I hope you’re having a great day. Thank you for reaching out, and I really appreciate you sharing the screenshot and details. 

Since you haven’t specified your account type (work/school vs. personal), I may not be able to provide an exact solution yet. Assuming you’re using a work account, please try the steps below. If you’re using a personal account, please let me know and I’ll tailor the guidance for that scenario.  
Step 1 - Retry and isolate the scope 

Click the Retry icon next to the failed message. 

Then send a short test message to a different contact. 

• If it works with others > the issue is likely specific to this contact/chat (or permission to message that user). 
• If it fails with everyone > likely desktop app/session/network/service. 

Try sending via Teams web or the mobile app. 

• If Web/Mobile works > likely desktop cache/session. 
• If Web/Mobile also fails > may be account/policy restriction or broader network/service issue. 

Step 2 - Restart Teams properly 

• Fully quit Teams (system tray icon > Quit), then reopen Teams and test again. 

Step 3 - Clear Teams cache (desktop) 

1. Quit Teams completely. 
2. Press Windows + R, then open the path below (whichever exists): 

%userprofile%\appdata\local\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeams 

1. Delete all files and folders in the directory, reopen Teams, sign in, and test again. 

More info here: Clear the Teams client cache - Microsoft Teams | Microsoft Learn 

Step 4 - Update Teams (and Windows) 

• Update Teams: In Teams, click Settings and more (…) > Check for updates. Wait for the update to finish, then quit Teams completely (system tray > Quit) and reopen Teams. 
• Update Windows: Go to Settings > Windows Update > Check for updates, install any pending updates, then restart your PC (this can help refresh WebView/network components used by Teams). 

Additionally, if this happens only with one contact: Please try delete the chat (if available) and message the contact again. If the contact is external/guest, external messaging may be restricted by your organization’s settings (external access/federation/domain rules). 

Step 5 - Contact your IT 
If you have tried all steps above and the problem persists, please contact your organization’s IT support team to verify your account status and Teams messaging policies (including external access/federation settings and any restrictions affecting chat delivery to that contact). They can also check for any tenant-level settings or service advisories impacting message delivery. 

IT admins can refer to this article: Use guest access and external access to collaborate with people outside your organization - Microso… 

In case your IT department cannot access the necessary information or make the required changes, I recommend asking them to open a request with Microsoft Support team through the Microsoft Admin Center. They have access to backend configurations and can perform a more in-depth investigation. At the very least, they can provide the most effective workaround to ensure your experience remains smooth and secure.     

As community moderators, we appreciate your understanding that we do not have access to the administrative tools or permissions required to investigate or modify these configurations. We also do not have the capability to initiate remote sessions for direct assistance. Our role is to guide users to the appropriate resources and support channels.  

I hope this information is helpful. Should you have any further questions or need additional assistance, feel free to reach out.  

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