How to merge two json object into an array in postgres

I have two jsonb value. I would like to merge it however I stuck to combine it together. This is my code

CREATE OR REPLACE FUNCTION emr.azintin(p_msg text)
 RETURNS character varying
 LANGUAGE plpgsql
AS $function$
DECLARE
    v_msgar     text[];
    v_msgln     text;
    v_currusr   afm_usr.user_id%type := 'SYSEXCH';
    v_currdt    afm_usr.insert_date%type := CURRENT_TIMESTAMP;
    macres      azt_macres%rowtype;
    orddet      lbt_orddet%rowtype;
    v_resultid  character varying ;
    v_reading   character varying ;

BEGIN   
         v_msgar := array['OBR||||^^^3972^2102001420||||20210227133222|25||||3
                            OBX|||0^RBC||4.99|^10â¶/μL|3.85-5.78||||F
                            OBX|||1^HGB||14.4|^g/dL|12.0-17.2||||F
                            OBX|||2^MCV||84.5|^fL|78.0-96.0||||F
                            OBX|||3^HCT||42.2|^%|34.8-50.9||||F
                            OBX|||4^MCH||28.90|^pg|26.40-33.20||||F
                            OBX|||5^MCHC||34.2|^g/dL|31.8-36.7|||<EOT>|F
                            OBX|||6^RDWsd||39.2|^fL|0.0-0.0||||F'];
              
            SELECT json_agg(jsonb_build_object('resultValue',split_part(parts[6],'^',1)))
               INTO v_reading
               FROM unnest(v_msgar) as elem,
                     regexp_split_to_array(elem, '\|') as parts
               WHERE parts[1] = 'OBX';
              
            SELECT json_agg(jsonb_build_object('resultId',split_part(parts[4],'^',2)))
               INTO v_resultid
               FROM unnest(v_msgar) as elem,
                     regexp_split_to_array(elem, '\|') as parts
               WHERE parts[1] = 'OBX';
              
            select concat(v_resultid || v_reading) 
               INTO macres.test_result
               FROM unnest(v_msgar) as elem,
                     regexp_split_to_array(elem, '\|') as parts
               WHERE parts[1] = 'OBX';
        
            SELECT split_part(items[5], '^', 5)
                  INTO macres.specimen_id
                FROM (
                  SELECT string_to_array(element, '|') as items
                 FROM unnest(v_msgar) as t(element)) t   
            WHERE items[1] = 'OBR';
    

    END IF;
END
$function$
;

I manage to get the v_reading and v_resultid which look like this

 [{"resultValue": "5.20"}, {"resultValue": "14.2"}, {"resultValue": "81.7"}, {"resultValue": "42.5"}, {"resultValue": "27.20"}, {"resultValue": "33.3"}, {"resultValue": "40.6"}, {"resultValue": "15.9"}, {"resultValue": "188"}, {"resultValue": "8.1"}, {"resultValue": "0.15"}, {"resultValue": "9.4"}, {"resultValue": "46.2"}, {"resultValue": "4.6"}, {"resultValue": "1.1"}, {"resultValue": "23.6"}, {"resultValue": "0.4"}, {"resultValue": "8.7"}, {"resultValue": "3.1"}, {"resultValue": "67.7"}, {"resultValue": "56"}, {"resultValue": "105"}, {"resultValue": ""}] 

[{"resultId": "RBC"}, {"resultId": "HGB"}, {"resultId": "MCV"}, {"resultId": "HCT"}, {"resultId": "MCH"}, {"resultId": "MCHC"}, {"resultId": "RDWsd"}, {"resultId": "RDWcv"}, {"resultId": "PLT"}, {"resultId": "MPV"}, {"resultId": "PCT"}, {"resultId": "PDWsd"}, {"resultId": "PDWcv"}, {"resultId": "WBC"}, {"resultId": "LYM"}, {"resultId": "LYMP"}, {"resultId": "MID"}, {"resultId": "MIDP"}, {"resultId": "GRA"}, {"resultId": "GRAP"}, {"resultId": "PLCR"}, {"resultId": "PLCC"}, {"resultId": "RBCHistogram"}]

how can i combine these two json to look like these

[{"resultid": "RBC", "resultValue": "5.20"}, {"resultid": "HGB", "resultValue": "5.20"}, {"resultid": "MCV", "resultValue": "5.20"}, {"resultid": "HCT", "resultValue": "5.20"}, {"resultid": "MCH", "resultValue": "5.20"}, {"resultid": "MCHC", "resultValue": "5.20"}, {"resultid": "RDWsd", "resultValue": "5.20"}, {"resultid": "RDWcv", "resultValue": "5.20"}, {"resultid": "PLT", "resultValue": "5.20"}, {"resultid": "MPV", "resultValue": "5.20"}, {"resultid": "PCT", "resultValue": "5.20"}, {"resultid": "PDWsd", "resultValue": "5.20"}, {"resultid": "PDWcv", "resultValue": "5.20"}, {"resultid": "WBC", "resultValue": "5.20"}, {"resultid": "LYM", "resultValue": "5.20"}, {"resultid": "LYMP", "resultValue": "5.20"}, {"resultid": "MID", "resultValue": "5.20"}, {"resultid": "MIDP", "resultValue": "5.20"}, {"resultid": "GRA", "resultValue": "5.20"}, {"resultid": "GRAP", "resultValue": "5.20"}, {"resultid": "PLCR", "resultValue": "5.20"}, {"resultid": "PLCC", "resultValue": "5.20"}, {"resultid": "RBCHistogram", "resultValue": "5.20"}]

I can simply do like these

            SELECT json_agg(jsonb_build_object('resultid',split_part(parts[4],'^',2), 'resultValue',split_part(parts[6],'^',1)))
               INTO macres.test_result
               FROM unnest(v_msgar) as elem,
                     regexp_split_to_array(elem, '\|') as parts
               WHERE parts[1] = 'OBX';

but the problem is I need to put a condition in split_part(parts[4],'^',2) thats why i seperate it into v_reading and v_resultid.

I want to put condition

IF v_resultid = 'MCHC' THEN
   v_reading = null
END ID

But somehow it still put the reading if the array found MCHC. I want to remove MCHC from my json