Why is my product page title not displaying in the browser tab?

[alonluciano]

Product page title not showing on the tab; URL is shown instead.

Please can anyone help me out? When viewing my website (https://togopower.jp/, the URL is shown in the browser tab instead of the shop title ‘TogoPower(トゴパワー)公式サイト - ポータブル電源, ソーラーパネル’, the same thing happens when I navigate to any of the other pages on my website. The product name should be shown on the browser tab but the URL is showing instead. Thank you in advance.

[Jason]

Have you made changes to the code in your theme? It looks like you are missing both the meta title and meta description elements.

They might have been removed by mistake so worth double checking the changes that have been made.

[alonluciano]

I installed the SEO enhanced app before, and then I deleted it. It may be related to this reason. So what should I do now?

This is the residual code file

[alonluciano]

Do I need to add a title to each page separately? Where should I modify it?

[alonluciano]

Could anyone please help me. thanks.