In order to resolve it, please follow steps below.
1. Login to your Erply POS
2. Click the "Cloud" Icon at the top panel on POS
3. Click the "Refresh Cache" in Products below the Cloud Icon
4. You may also click the "Trash" Icon to clear and resync cache from the scratch
5. You may also Sync Products in POS Settings > Configuration > Local database support > “Reset local products database” then save.