Colleagues haven't sent invitations here because you said that if you sent an invitation, it is basically equivalent to giving a "fine" directly, so they won't be able to come! You can say hello to them in advance and say when to invite them to dinner!

After your wedding, you can hold a thank-you banquet here! The scale of the thank-you banquet depends on your own ideas.

If you want to collect red envelopes and return to your hometown, you can ask the wedding etiquette company to make a simple cloth field to create the atmosphere of the wedding reception.

If you just want to treat everyone to a meal and maintain a relationship, then find a small restaurant with good taste and treat everyone to a meal!