"Cannot POST" error

Question

My code makes the mistake:

Cannot POST /save-Institution

when I click send in the form

server.js:

        const express=require('express');
        const path=require('path');
        const pages=require('./pages.js');

        const server=express();
        server
            .use(express.urlencoded({extended:true}))

            .use(express.static('public'))

            .set('views', path.join(__dirname, 'views'))
            .set('view engine', 'hbs')

            .get('/', pages.index)
            .get('/adotar', pages.adotar)
            .get('/instituicoes', pages.instituicoes)
            .get('/instituicao', pages.instituicao)
            .get('/cadastrarinsti', pages.cadastrarInst)
            .get('/save-instituicao', pages.saveInstituicao);


        server.listen(5500, () => {
            console.log("Server started");
        });

pages js.

        const Database=require('./database/db');
        const saveInstituicao=require('./database/saveInstituicao');

    module.exports={
    
    index(req, res){
        return res.render('index');
    },

    async adotar(req, res){
        try{
            const db=await Database;
            const instituicoes=await db.all("SELECT * FROM adotar");
            return res.render("adotar", { adotar });
        } catch (error) {
            console.log(error);
            return res.send('Erro no banco de dados');
        }
    },

    async instituicao(req, res){

        const id= req.query.id;

        try{
            const db=await Database;
            const results=await db.all(`SELECT * FROM instituicoes WHERE id="${id}"`);
            const instituicao= results[0]
            instituicao.images= institiuicao.images.split(",");
            instituicao.firstImage=instituicao.images[0];
            
            return res.render("instituicao", { instituicao: instituicao[0] });
        } catch (error) {
            console.log(error);
            return res.send('Erro no banco de dados');
        }
    },

    async instituicoes(req, res){
        try{
            const db=await Database;
            const instituicoes=await db.all("SELECT * FROM instituicoes");
            return res.render("instituicoes", { instituicoes });
        } catch (error) {
            console.log(error);
            return res.send('Erro no banco de dados');
        }
    },

    cadastrarInst(req, res){
        return res.render('cadastrarinst');
    },

    async saveInstituicao(req, res){
        const fields = req.body;

        if(Object.values(fields).includes('')){
            return res.send('Todos os campos devem ser preenchidos');}
        try {
            await saveInstituicao(db,{
                name:fields.name,
                about:fields.about,
                address:fields.address,
                telephone:fields.telephone,
                images:fields.images.toString(),
                opening_hours:fields.opening_hours,
            })
            return res.redirect('/instituicoes')
        } catch (error) {
            console.log(error)
            return res.send('Erro no banco de dados')
        }
       }  
     }

html

        <form action="save-institution" method="post">

                <fieldset>
                  <legend>Informações da Instituição</legend>
        
                  <div class="input-block">
                    <label for="name">Nome</label>
                    <input id="name" name="name" required />
                  </div>
        
                  <div class="input-block">
                    <label for="about">Sobre <span>Máximo de 300 caracteres</span></label>
                    <textarea id="about" name="about" required></textarea>
                  </div>
        
                  <div class="input-block">
                    <label for="telephone">Telefone/Celular</label>
                    <input id="telephone" name="telephone" required />
                  </div>
        
                  <div class="input-block images">
                    <label for="images">Fotos</label>
                    <div class="images-upload" id="images">
                      <div class="new-upload">
                        <input name="images" placeholder="Cole o link da foto aqui" required type="url" />
                        <span onclick="deleteField(event)">
                          <img src="/images/remove-file.svg" alt="Remover Foto" />
                        </span>
                      </div>
                    </div>
                    <button onclick="addPhotoField()" type="button">
                      <img src="/images/add-file.svg" alt="Adicionar foto" />
                    </button>
                  </div>
    
                  <div class="input-block">
                    <label for="opening_hours">Horário de Atendimento</label>
                    <input id="opening_hours" name="opening_hours" required />
                  </div>
                  <div>
                    <button type="submit" class="primary-button">Confirmar</button>
                  </div>
                </fieldset>
              </form>