Need to get the a value from a specific nested json element using MySQL

Question

Answers to a questionnaire are stored in json in a column in this table. I need to pull out the answer to a specific question stored within this column, but am struggling to do so.

I want to get the postValue '123456789' as 'Incorporation Number'

I am not sure how to get the specific child element value - any help much appreciated.

select json_extract(table.json_column, '$.user_data.element.postValue') as 'json' 
from table
where table.id = 123

the json looks something like the below:

{
   "risk_data":[
      
   ],
   "user_data":[

       "elements":[
            {
               "postName":"postNameInput",
               "postValue":"TEST COMPANY"
            }
         ],
         "language":"english",
         "elementId":"100",
         "sectionId":"9",
         "weightage":null,
         "isHyperLink":0,
         "elementIndex":0,
         "elementTitle":{
            "english":"Company's Full Legal Name"
         },
         "hyperLinkUrl":null,
         "isWorkFlowNa":0,
         "sectionIndex":0,
         "sectionTitle":{
            "english":"Basic Company Information"
         },
         "hyperLinkText":null,
         "isMultiSelect":0,
         "selectedChart":null,
         "dataAttributes":null,
         "elementTitleAbb":{
            "english":"Company's Full Legal Name"
         },
         "isHiddenElement":0,
         "isHiddenSection":0,
         "elementInputType":"input",
         "elementFooterText":null,
         "elementHeaderText":null,
         "elementDescription":null,
         "hyperLinkTextAfter":null,
         "question_abb_table":null,
         "hyperLinkTextBefore":null,
         "enableSelfReportingForManageThirdParty":0,
         "enableSelfReportingForThirdPartyProfile":0
      }, {
         "elements":[
            {
               "postName":"postNameInput",
               "postValue":"123456789"
            }
         ],
         "language":"english",
         "elementId":"101",
         "sectionId":"10",
         "weightage":null,
         "isHyperLink":0,
         "elementIndex":4,
         "elementTitle":{
            "english":"Incorporation Number"
         },
         "hyperLinkUrl":null,
         "isWorkFlowNa":0,
         "sectionIndex":3,
         "sectionTitle":{
            "english":"Organisational Structure"
         },
         "hyperLinkText":null,
         "isMultiSelect":0,
         "selectedChart":null,
         "dataAttributes":null,
         "elementTitleAbb":{
            "english":"Incorporation Number"
         },
         "isHiddenElement":0,
         "isHiddenSection":0,
         "elementInputType":"input",
         "elementFooterText":null,
         "elementHeaderText":null,
         "elementDescription":null,
         "hyperLinkTextAfter":null,
         "question_abb_table":null,
         "hyperLinkTextBefore":null,
         "enableSelfReportingForManageThirdParty":0,
         "enableSelfReportingForThirdPartyProfile":0
      },