Create condition on the state of a custom field

[Askancy]

I'm trying to create a condition for a custom field in the user profile, in my case I have two fields, field_25 and field_26.

field_25 = input
field_26 = checkbox

I would need that if field_26 is equal to 1 it adds an emoji.

In the template customFieldsDisplay I wrote:

{{if \IPS\Db::i()->select('field_26', 'core_pfields_content')->where('member_id', $author->member_id)->first() == '1'}}
    check
{{else}}
    no
{{endif}}

but I get the error: [[Template core/front/global/customFieldsDisplay is throwing an error. This theme may be out of date. Run the support tool in the AdminCP to restore the default theme.]]

where is my mistake?