Performance degradation on Android and iOS switching between scenes

I have a very simple game in which the player, from the main game scene, can click a button to load an inventory scene.
In this inventory scene, I have only a Scroll View that gets populated at runtime with something like the following:

foreach (var c in coins)
            coin = Instantiate(coinTemplate);            
            coin.transform.SetParent(content.transform, false);
            // some other stuff on this coin

In Editor everything works perfectly, the issue is that on Android and on iOS I have very bad performance degradation every time the user switches between the two scenes. So the first time the inventory gets loaded game performance is normal, it gets slower after 2 or 3 times and unusable after 7 o 8 times.

Could it be a garbage collection problem?

I have tried to follow suggestions from the following link, but it didn’t help:

Can you send the entire method of this code and also the method that call this one?
and, usually, how many items are loaded in this foreach?

The solution was to keep the inventory always in memory, and switch between the scenes with LoadSceneMode.Additive.