Hi!!

Okay so first, welcome to the site! We have loads of experienced guinea pig owners who can help answer questions and give suggestions as needed.

Second, stop the play time visits. It's very stressful for pigs to be put together then taken apart repeatedly. They have to start over establishing dominance each time they are put together.

The only time they should be interacting is during introductions and once they have been introduced and are living together. Take time to do proper introductions. It can take a while so be prepared to carve out at least a few hours of time but it will take as long as it need to take for them to be able to at least tolerate each other.

Before even doing introductions though, you have to make 100% sure they are both the same gender. You can post a close up picture of each pig's genital region and we can help you determine gender for each.

You also have to make sure that the cage you have is large enough for two pigs, especially if you have two males.

Here is a bit of information to get you started:
Info on C&C cages:https://www.guineapigcages.com/cubes.htm
https://www.guineapigcages.com/index.htm
@bpatters and @lissie will also have some great information for new pig owners.

Again, welcome!

https://pethelpful.com/rodents/5-Most-Common-Guinea-Pig-Owner-Mistakes

I highly recommend reading the article I posted above, it is very helpful. Hopefully, you won't make the same mistakes!!!!