(Solved) Emails sent from WordPress to Gmail are not being sent [Lollipop]

There have been cases where emails sent from WordPress could not be received only by Gmail.
I've been getting a lot of similar inquiries lately.

This time, I would like to introduce the way I solved the problem using Lolipop.
I understand that it won't necessarily work perfectly depending on how you operate your server, but I hope this information will be helpful.

Needs to be set to MuuMuu DNS

First, you need to set up your domain using MuuMuu DNS.

Log in to Lolipop and click the "Migrate to MuuMuu DNS" button on the left sidebar.
If you have already been migrated, it will say "Using Muumuu DNS" as shown in the attached image, so you can leave the settings as they are.

Setting up with MuuMuuDomain

After changing the settings to Muumuu DNS, you will work on Muumuu Domain.
Log in to the MuuMuu Domain control panel.

Open MuuMuu DNS and click the [Change] button for the domain you want to set.

SFP Settings

Setting 2 Enter the following information to set up your custom settings:

[Subdomain] Blank
[Type] TXT
[Content] v=spf1 include:_spf.lolipop.jp ~all

For subdomains

For subdomains, enter the subdomain string in the subdomain field.
Example: If your subdomain is memer.hanami-web.tokyo, enter "member" in the subdomain field.

[Subdomain] Subdomain name
[Type] TXT
[Content] v=spf1 include:_spf.lolipop.jp ~all

Finally, click the [Change Setup Information] button to finish.
It may take up to an hour for the changes to be reflected.

[Advanced] You can check the TXT settings with the command prompt.

This is a Windows method, but you can check if the TXT settings have been added using the command prompt.

Search for Windows and open Command Prompt.

nslookup -type=TXT domain you want to look up

The output will look like this, confirming that the SPF settings have been applied.