Change template for repeater items and field after 1062 Duplicate entry error

[Zeka]

While creating repeater field I got this exception after pressing of save button

SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry 'repeater_product_shop_animal_groups_list' for key 'name'

I'm sure that there wasn't template with this name. After that, there was no details tab on the field editing page, so I pressed save button again and it went right. After creating some content and writing markup for this field I've discovered that for this repeater field assigned template with name 'repeater_product_shop_animal_groups_list1'.

Currently, there is one field and two templates 'repeater_product_shop_animal_groups_list' and 'repeater_product_shop_animal_groups_list1' and all created repeater items are using 'repeater_product_shop_animal_groups_list1' template.

I've found several similar threads on the forum, but still don't understand what caused this error. 

What would be the easiest way to change a template for created items and reassign template for this repeater field to desirable one?