Error: Unable to setup base domain mappings for api.picturethis.xyz

Serverless Framework
1

I have used the suggestions from StackOverflow

but the error remains

Error: Unable to setup base domain mappings for api.picturethis.xyz

service: picture-this-api

frameworkVersion: '2'

plugins:
  - serverless-domain-manager

custom:
  customDomain:
    domainName: api.picturethis.xyz
    basePath: 'v1'
    stage: ${self:provider.stage}
    certificateName: picturethis.xyz
    createRoute53Record: true

provider:
  name: aws
  runtime: go1.x
  lambdaHashingVersion: 20201221
  stage: ${opt:stage, 'dev'} 
  region: us-east-1

package:
  patterns:
    - '!./**'
    - ./bin/**

functions:
  testimonials:
    handler: bin/testimonials
    events:
      - httpApi:
          path: /testimonials
          method: get