submit thumbnails – customized picture measurement not being displayed in loop

I imagine I am lacking one thing on media photos.

I’ve created a customized picture measurement with this code:

add_image_size( '250-square', 250, 250, true); // cropped

I’ve then uploaded photos. After I examine within the applicable uploads listing in my set up I see that the picture is uploaded and totally different sizes have been created.

I’ve set my thumbnail dimensions to 75×75 arduous crop in order that there will likely be 2 totally different photos with a 1:1 ratio if a picture is uploaded that isn’t 1:1 as it’s my understanding that is wanted to create a srcsest.

For instance I uploaded a picture (myimage.png) with dimensions of 1507 × 1267.

Within the listing I’ve:

• myimage.png
• myimage-75×75.png
• myimage-250×250.png
• myimage-400×400.png
• myimage-1200×1200.png
• myimage-768×336.png
• myimage-1024×861.png
• myimage-1507×500.png

In my loop I am calling the thumbs with this code:

<div class="product_cat <?php echo $kidcount;?>"> //simply outputs what number of youngsters are within the class
    <a href="<?php the_permalink();?>">
        <?php the_post_thumbnail('250-square');?>                 
        <h2><?php echo get_the_title();?></h2>
    </a>
</div>

Nevertheless that is what’s being generated:

<div class="productCategories grid">
    <div class="product_cat 5">
        <a href="https://examplesite.com/merchandise/biglight-36-4000-landing-light/">
            <img src="https://examplesite.com/wp-content/uploads/2020/10/aeroleds-biglight-4000-landing.png" class="attachment-250-square size-250-square wp-post-image" alt="A picture of Aeroleds biglight 4000 Touchdown" width="250" top="210">
            <h2>biglight 36-4000</h2>
        </a>
    </div>
    <div class="product_cat 5">
        <a href="https://examplesite.com/merchandise/biglight-36-4000-taxi-light/">
            <img src="https://examplesite.com/wp-content/uploads/2020/10/biglight_36_4587_4314_Taxi_SH.png" class="attachment-250-square size-250-square wp-post-image" alt="A picture of biglight 36 4587 4314 Taxi Sh" loading="lazy" srcset="https://examplesite.com/wp-content/uploads/2020/10/biglight_36_4587_4314_Taxi_SH.png 450w, https://examplesite.com/wp-content/uploads/2020/10/biglight_36_4587_4314_Taxi_SH-75x75.png 75w" sizes="(max-width: 250px) 100vw, 250px" width="250" top="250">
            <h2>biglight 36-4000</h2>
        </a>
    </div>
</div>

The primary picture does not generate a srcset and is not loading at 250×250 nor does it name the 250×250 model of the picture. the remainder of the photographs (i eliminated them for simplicity on this query) work because the 2nd picture within the output proven right here.