Spring are a low cost carrier, and similar to others in the region, you must assume that they will enforce the 7kg weight and size for the cabin bag.

Some other low cost carriers in the region offer more cabin luggage of you buy a premium seat, but I have no experience of Spring so you would need to check all the available options that they're offering to upsell on your route. This page suggests you can get 10kg with Spring Plus whatever that is.

https://en.ch.com/flights/excess-baggage

If it's a smaller aircraft like an ATR it might be a operational restriction.
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