Hi! In my custom purchase module i have quite complicated setup. Unfortunately, once i'm trying to save RFQ with any product inside, system replies with an error:

The operation cannot be completed, probably due to the following:
- deletion: you may be trying to delete a record while other records still reference it
- creation/update: a mandatory field is not correctly set

[object with reference: name - name]

Here is everything i have inside custom models.py regarding name:

@api.multi
    def get_data_sum(self, field_name):
        data_list = [getattr(line, field_name) for line in self.order_line]
        return sum(data_list)
    def add_product(self, rec, product_ids):
        for product_id in product_ids:
            pro_ref = self.env['product.product'].search([('id','=',product_id)])
            name = pro_ref.name
            uom = pro_ref.uom_id.id
            val = {
                    'order_id': rec.id,
                    'name': name,
                    'product_qty': 1,
                    'date_planned': datetime.now(),
                    'product_uom': uom,
                    'price_unit': 0.0,
                    'product_id': product_id,
                    }
            self.env['purchase.order.line'].create(val)

and

    @api.onchange('product_id')
    def onchange_product_id(self):
        rec = super(PurchaseOrderLine, self).onchange_product_id()
        name = self.product_id.name
        self.update({'name': name})
    @api.multi
    @api.onchange('product_id', 'alt_uom', 'display_product_qty', 'price_alt_uom', 'packaging')
    def _get_unit_price(self):
        '''Function to calculate every automated value on pol'''
        if self.product_id.type == 'service' or self.product_id.type == 'consu':
            self.alt_uom = False
            self.product_qty = self.display_product_qty
            self.price_unit = self.price_alt_uom
        else:
            if self.product_id.uom_group.name:
                if self.alt_uom == 'm3':
                    if self.product_id:
                        name = self.product_id.uom_group.name.split('x')
                        alt_uom_ratio = 1
                        total_m3 = (float(name[0])*float(name[1])*float(name[2])*self.display_product_qty * self.packaging.uom_value)/1000000000
                        self.volm = total_m3
                        self.price_unit = alt_uom_ratio * self.price_alt_uom
                        self.price_subtotal = total_m3 * self.price_alt_uom
                        self.product_qty = total_m3
                
                elif self.alt_uom == 'pc':
                    if self.product_id:
                        name = self.product_id.uom_group.name.split('x')
                        alt_uom_ratio = 1/((float(name[0])*float(name[1])*float(name[2]))/1000000000)
                        total_pcs = self.display_product_qty * self.packaging.uom_value
                        self.volm = total_pcs
                        self.price_unit = alt_uom_ratio * self.price_alt_uom
                        self.price_subtotal = total_pcs * self.price_alt_uom
                        self.product_qty = (float(name[0])*float(name[1])*float(name[2])*self.display_product_qty * self.packaging.uom_value)/1000000000
                elif self.alt_uom == 'm2':
                    if self.product_id:
                        name = self.product_id.uom_group.name.split('x')
                        alt_uom_ratio = 1/(float(name[0])/1000)
                        total_m2 = (float(name[1])*float(name[2])*self.display_product_qty*self.packaging.uom_value)/1000000
                        self.volm = total_m2
                        self.price_unit = alt_uom_ratio * self.price_alt_uom
                        self.price_subtotal = total_m2 * self.price_alt_uom
                        self.product_qty = (float(name[0])*float(name[1])*float(name[2])*self.display_product_qty * self.packaging.uom_value)/1000000000
                    
                elif self.alt_uom == 'ft2':
                    if self.product_id:
                        name = self.product_id.uom_group.name.split('x')
                        alt_uom_ratio = 1/((float(name[0])/1000)*10.76391041)
                        total_ft2 = (float(name[1])*float(name[2])*self.display_product_qty*self.packaging.uom_value)*10.76391041/1000000
                        self.volm = total_ft2
                        self.price_unit = alt_uom_ratio * self.price_alt_uom
                        self.price_subtotal = total_ft2 * self.price_alt_uom
                        self.product_qty = (float(name[0])*float(name[1])*float(name[2])*self.display_product_qty * self.packaging.uom_value)/1000000000
                elif self.alt_uom == 'msf':
                    if self.product_id:
                        name = self.product_id.uom_group.name.split('x')
                        alt_uom_ratio = 1/((float(name[0])/1)*10.76391041)
                        total_msf = (float(name[1])*float(name[2])*self.display_product_qty*self.packaging.uom_value)*10.76391041/1000000000
                        self.volm = total_msf
                        self.price_unit = alt_uom_ratio * self.price_alt_uom
                        self.price_subtotal = total_msf * self.price_alt_uom
                        self.product_qty = (float(name[0])*float(name[1])*float(name[2])*self.display_product_qty * self.packaging.uom_value)/1000000000

Please share any of your thoughts.