You can perform a rescan in the menu settings of the mobile wallet. The wallet will then check the entire blockchain looking for transactions that belong to this wallet.
If that does not produce the desired result, it is likely that you are using a recovery phrase that was initially created on a desktop. A recovery sentence from a desktop does not work well on a mobile and will show incorrect or incomplete transactions. It does work the other way around, a mobile recovery sentence does work well on a desktop.
So the best thing you can do then is restore the wallet on a desktop.
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