the issue you're facing is likely due to the fact that all your setup models have the same field name (name) and therefore the same database column name in the underlying database table. This is causing conflicts when creating the SQL constraints for uniqueness.
To ensure that the constraints are unique for each setup model, you can include the model name in the constraint name and error message. This way, each constraint will have a unique name, avoiding conflicts. Here's how you could modify your code:

try this way:

class DonationCategory(models.Model):

_name = 'your_module.donation.category'

_description = 'Donation Category'

name = fields.Char(string='Name', required=True)

_sql_constraints = [

('donation_category_name_unique',

'UNIQUE(name)',

"Donation Category Name must be unique"),

]

class DonationType(models.Model):

_name = 'your_module.donation.type'

_description = 'Donation Type'

name = fields.Char(string='Name', required=True)

_sql_constraints = [

('donation_type_name_unique',

'UNIQUE(name)',

"Donation Type Name must be unique"),

]