Hi, anyone can you please advise how can I limit people to Post Ad and can only type a maximum 15 characters in Phone Number field?

Hi, anyone can you please advise how can I limit people to Post Ad and can only type a maximum 15 characters in Phone Number field?

in item-post.php

1. find:
<?php if(strpos($required_fields, 'phone') !== false) { ?>
          sPhone: {
            required: true,
            minlength: 6
          },
         
replace with:
<?php if(strpos($required_fields, 'phone') !== false) { ?>
          sPhone: {
            required: true,
            minlength: 6,
            maxlength: 15
          },
2. find:
<?php if(strpos($required_fields, 'phone') !== false) { ?>
          sPhone: {
            required: "<?php echo osc_esc_js(__('Phone: this field is required.', 'veronika')); ?>",
            minlength: "<?php echo osc_esc_js(__('Phone: enter at least 6 characters.')); ?>"
          },
          <?php } ?>
replace with:
 <?php if(strpos($required_fields, 'phone') !== false) { ?>
          sPhone: {
            required: "<?php echo osc_esc_js(__('Phone: this field is required.', 'veronika')); ?>",
            minlength: "<?php echo osc_esc_js(__('Phone: enter at least 6 characters.')); ?>",
            maxlength: "<?php echo osc_esc_js(__('Phone: max 15 characters.')); ?>"
          },
          <?php } ?>

how to make it that it so it wont allow letters

how to make it that it so it wont allow letters

Use mask
https://igorescobar.github.io/jQuery-Mask-Plugin/

wow thank you,   

i tried to do it, its not working for me, can you help me?

copy script on server and show location in header.
I did tried few month ago for testing, and working good, if i remember there are 2 scripts, you need smallest one. 

thank you, its working