NoMethodError undefined method formats for modify:String

=> Booting Puma
=> Rails 5.2.1 application starting in development
=> Run `rails server -h` for more startup options
Puma starting in single mode...
* Version 3.12.0 (ruby 2.5.3-p105), codename: Llamas in Pajamas
* Min threads: 5, max threads: 5
* Environment: development
* Listening on tcp://0.0.0.0:3000
Use Ctrl-C to stop
Started GET "/purchase_orders/modify?prid=1" for 127.0.0.1 at 2019-03-22 13:26:41 +0800
   (0.4ms)  SELECT "schema_migrations"."version" FROM "schema_migrations" ORDER BY "schema_migrations"."version" ASC
  ↳ /home/sysadmin/.rbenv/versions/2.5.3/lib/ruby/gems/2.5.0/gems/activerecord-5.2.1/lib/active_record/log_subscriber.rb:98
Processing by PurchaseOrdersController#modify as HTML
  Parameters: {"prid"=>"1"}
  PurchaseRequest Load (0.3ms)  SELECT  "purchase_requests".* FROM "purchase_requests" WHERE "purchase_requests"."id" = $1 LIMIT $2  [["id", 1], ["LIMIT", 1]]
  ↳ app/controllers/purchase_orders_controller.rb:20
  PurchaseOrder Load (0.8ms)  SELECT  "purchase_orders".* FROM "purchase_orders" WHERE "purchase_orders"."purchase_request_id" = $1 ORDER BY "purchase_orders"."id" ASC LIMIT $2  [["purchase_request_id", 1], ["LIMIT", 1]]
  ↳ app/controllers/purchase_orders_controller.rb:21
  Rendering purchase_orders/modify.slim within layouts/application
  Rendered partials/_nav_pr.slim (13.7ms)
  PurchaseOrder Load (0.3ms)  SELECT "purchase_orders".* FROM "purchase_orders" WHERE "purchase_orders"."purchase_request_id" = $1  [["purchase_request_id", 1]]
  ↳ app/views/purchase_orders/modify.slim:38
  Rendered purchase_orders/modify.slim within layouts/application (60.7ms)
  Rendered partials/_top_nav.slim (9.6ms)
Completed 200 OK in 408ms (Views: 372.4ms | ActiveRecord: 6.2ms)


Started GET "/po/1.pdf" for 127.0.0.1 at 2019-03-22 13:26:57 +0800
Processing by PurchaseOrdersController#report_pdf as PDF
  Parameters: {"id"=>"1"}
  PurchaseOrder Load (0.2ms)  SELECT  "purchase_orders".* FROM "purchase_orders" WHERE "purchase_orders"."id" = $1 LIMIT $2  [["id", 1], ["LIMIT", 1]]
  ↳ app/pdfs/purchase_order_report_pdf.rb:8
  PurchaseRequest Load (0.3ms)  SELECT  "purchase_requests".* FROM "purchase_requests" WHERE "purchase_requests"."id" = $1 LIMIT $2  [["id", 1], ["LIMIT", 1]]
  ↳ app/pdfs/purchase_order_report_pdf.rb:9
  Abstract Load (0.3ms)  SELECT  "abstracts".* FROM "abstracts" WHERE "abstracts"."purchase_request_id" = $1 LIMIT $2  [["purchase_request_id", 1], ["LIMIT", 1]]
  ↳ app/pdfs/purchase_order_report_pdf.rb:10
PDF's built-in fonts have very limited support for internationalized text.
If you need full UTF-8 support, consider using a TTF font instead.

To disable this warning, add the following line to your code:
Prawn::Font::AFM.hide_m17n_warning = true
  AbstractItem Load (0.5ms)  SELECT "abstract_items".* FROM "abstract_items" WHERE "abstract_items"."abstract_id" = $1 AND "abstract_items"."awardee" = $2  [["abstract_id", 1], ["awardee", "KING LEE ENTERPRISES"]]
  ↳ app/pdfs/purchase_order_report_pdf.rb:129
  PurchaseRequestItem Load (0.3ms)  SELECT  "purchase_request_items".* FROM "purchase_request_items" WHERE "purchase_request_items"."id" = $1 LIMIT $2  [["id", 2], ["LIMIT", 1]]
  ↳ app/pdfs/purchase_order_report_pdf.rb:130
  Rendering text template
  Rendered text template (0.0ms)
Sent data  (1.0ms)
Completed 200 OK in 537ms (Views: 0.9ms | ActiveRecord: 7.7ms)


Started GET "/purchase_orders/modify?prid=1" for 127.0.0.1 at 2019-03-22 13:27:11 +0800
Processing by PurchaseOrdersController#modify as HTML
  Parameters: {"prid"=>"1"}
  PurchaseRequest Load (0.2ms)  SELECT  "purchase_requests".* FROM "purchase_requests" WHERE "purchase_requests"."id" = $1 LIMIT $2  [["id", 1], ["LIMIT", 1]]
  ↳ app/controllers/purchase_orders_controller.rb:20
  PurchaseOrder Load (0.2ms)  SELECT  "purchase_orders".* FROM "purchase_orders" WHERE "purchase_orders"."purchase_request_id" = $1 ORDER BY "purchase_orders"."id" ASC LIMIT $2  [["purchase_request_id", 1], ["LIMIT", 1]]
  ↳ app/controllers/purchase_orders_controller.rb:21
Completed 500 Internal Server Error in 6ms (ActiveRecord: 0.5ms)



NoMethodError (undefined method `formats' for "modify":String
Did you mean?  form_tag):

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actionview (5.2.1) lib/action_view/renderer/renderer.rb:44:in `render_template'
actionview (5.2.1) lib/action_view/renderer/renderer.rb:25:in `render'
actionview (5.2.1) lib/action_view/rendering.rb:103:in `_render_template'
actionpack (5.2.1) lib/action_controller/metal/streaming.rb:219:in `_render_template'
actionview (5.2.1) lib/action_view/rendering.rb:84:in `render_to_body'
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actionpack (5.2.1) lib/action_controller/metal/renderers.rb:142:in `render_to_body'
actionpack (5.2.1) lib/abstract_controller/rendering.rb:25:in `render'
actionpack (5.2.1) lib/action_controller/metal/rendering.rb:36:in `render'
actionpack (5.2.1) lib/action_controller/metal/instrumentation.rb:46:in `block (2 levels) in render'
activesupport (5.2.1) lib/active_support/core_ext/benchmark.rb:14:in `block in ms'
/home/sysadmin/.rbenv/versions/2.5.3/lib/ruby/2.5.0/benchmark.rb:308:in `realtime'
activesupport (5.2.1) lib/active_support/core_ext/benchmark.rb:14:in `ms'
actionpack (5.2.1) lib/action_controller/metal/instrumentation.rb:46:in `block in render'
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actionpack (5.2.1) lib/action_controller/metal/instrumentation.rb:45:in `render'
actionpack (5.2.1) lib/action_controller/metal/implicit_render.rb:35:in `default_render'
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actionpack (5.2.1) lib/action_controller/metal/basic_implicit_render.rb:6:in `send_action'
actionpack (5.2.1) lib/abstract_controller/base.rb:194:in `process_action'
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puma (3.12.0) lib/puma/thread_pool.rb:133:in `block in spawn_thread'