Single post template not being used

Hi guys

I have a default vanilla post category of relief-fund and tried creating a template file called single-post-relief-fund.php that I understood from the docs that the hierarchy should be used to display that category. I reproduced it below:

The single post template file is used to render a single post. WordPress uses the following path:

single-{post-type}-{slug}.php – (Since 4.4) First, WordPress looks for a template for the specific post. For example, if post type is product and the post slug is dmc-12, WordPress would look for single-product-dmc-12.php.
single-{post-type}.php – If the post type is product, WordPress would look for single-product.php.
single.php – WordPress then falls back to single.php.
singular.php – Then it falls back to singular.php.
index.php – Finally, as mentioned above, WordPress ultimately falls back to index.php.

However, the template being used is single.php and it ignores the specific one. I have checked the db and post-type is definitely ‘post’. Am I missing something?

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