Plants dying in Pets at Home tank

[BooseysMom]

Hi
I have a 40l tank from Pets at Home. It looks great as it's panoramic but I'm not convinced the lights are up to scratch as my plants don't seem to grow and the wisteria looks awful and is virtually dead. (I'll try and attach a photo) I've looked at upgrading the lights but not sure what to go for and whether I should completely replace the standard lights or add an extra one somehow. Has anyone else had the same issue? I feel like I'm chucking money at it by buying more plants that never grow.
Thanks

Hey, I have the same tank as a quarantine so I don't really use it for plants but it's not the best lighting however it's not the worst either. Have you been adding liquid ferts and root tabs? Do you have other plants growing?

ChickenGotLegs. Thanks for your post. Yes, I forgot to say that I've been using Root Tabs and liquid CO2 (couple of squirts per day) as advised by the shop. I have noticed burn marks on some of the Amazon sword plants and would be surprised if it's the light causing it. Maybe it's the CO2?
Yes, I have added a few smaller plants and they aren't dying Luke the wisteria. They have a very tiny amount of growth.
Do you think I need deeper substrate as I think it's only about an inch and a half deep?
I inherited the tank from my dad who has a bigger one now.