Weird white accent on 1.8" TFT SPI Display (solved)

I'm currently building a CNC Plotter robot and purchased a 1.8" TFT ST7735 Display to make a small menu for it. I have a setup with a L7805 5v tension regulator which feeds both the Arduino and a small 3.3v 662K regulator, which in turn feeds the screen. However, whenever I turn the screen on I get this weird white accent and lines (see picture), which only goes away if I start feeding the arduino via my laptop's USB while keeping the screen fed by the regulator. If I feed the screen directly from the arduino I also get this problem.

I'm using the Adafruit library and my Arduino is a clone, if that makes any difference.

Normal state of the screen:

Did you build this project without any reference schematic in hand? Your problem report suggests power problems but we can't see any of that, what you did.

Unless I misunderstand, you did not say under what conditions the "normal state of the screen" exists.

Your laptop provides a ground through the USB cable. Check your ground wires.

I didn't have any schematics when building but I made this drawing which I hope clears everything up

In this case the screen presents the problem

And in this case the screen functions normally

I'd like the robot to function independently from USB, so the later case isn't ideal for me

I checked them but still couldn't find any issues

Why are you applying 3.3v to the display if the pin is labeled "5v" ?

Addition
The soldering of the display's pins not looks good in the picture...

Inexplicable, as there is no GND connection from UNO to display.

Sorry, that was just a mistake in my drawing. In real life its labeled 3.3V.

As for the soldering, it appeared kinda weird in that picture because of lighting, but usually looks like this

That's what I thought. It's really weird

Please provide a link to the display you bought. We need to know if it is for 3.3V or 5V supply and data lines.
If your display is for 3.3V - as usual for these - then your effects are to be expected. Because you may feed it with 5V through your data lines.

The site doesn't give much information (and is in portugese because that's my country's language), but anyways here is it:
https://shopee.com.br/Módulo-De-Tela-LCD-IPS-3-3v-1-8-Polegadas-Série-128-*-128-128-*-160-65K-SPI-Cor-Completa-TFT-Substituir-OLED-ST7735-i.839380864.18837109518

It seems, however, that the data lines are also 3.3V, so the issue is probably what you said.

I'll buy some components to turn the arduino 5V signal into a 3.3V one, and if that works I'll give an update. Thank you really much.

I got a 5v to 3.3v logic level converter and now the screen is working flawlessly. I'm really grateful for your help.

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