Main page showing custom domain, but 3 other pages showing as .squarespace on google search engine

Hi everyone,

My website is using a custom domain as primary and when I navigate through my site all pages show the custom domain, but when Googling my business the first result is my main page under the custom domain, then the 3 other pages come up as .squarespace domains with the main title being Squarespace, I don't know why this is happening, does anyone know how I can rectify this please?

Thanks. 

I contacted Squarespace who advised me to check Google Console setting, I have indexed all the pages under my custom domain but still they show up under the .squarespace domain, anyone know how to fix this? Thank you.

Can you share site url & some screenshot of Google result?