How to upgrade old prepaid sim to LTE sim

I'm not that techie and not really into gadgets. I'm not the type who won't last a day without a cellphone. The millennial world of gadgets didn't even force me to spend money and compete with the people around me. It actually posed a problem with everyone who was trying to contact me.
Then last year, the 3+ year-old Starmobile phone that I was using just reached its end of life. It compelled me to buy a new Oppo phone which I hope will last for at least 5 years. My old phone has a regular SIM slot while the new phone uses a nano SIM. Me being so lazy to go out of the house, I spend 50 php to be able to keep the same number by asking my sister to have my SIM cut at the store where they will buy a new phone for my cousin. Unfortunately, the new phone didn't solve the communication problems. So I figured the prepaid TM SIM might be the cause and confirmed it by accessing the LTE checker on the *143# menu.

Finally, I decided to visit a Globe outlet inside a mall for a SIM uograde. I approached the personnel in charged of the queueing and waited patiently for my turn. There's a monitor where customers' names are flashed but some of us were just called by the staff themselves.

What happened during my turn:
1. The lady asked for my 2 valid IDs, photocopied it and asked me to sign three times. Luckily, I brought my passport and PRC ID with me even if I wasn't aware of these requirements.
2. I answered a form given by the lady who assisted me. She (mis)called my number to verify.

Answer the items with the check marks.

3. The lady asked me to send UPGRADE to 8080. I received an SMS containing the upgrade code thereafter.

4. She asked me my last loading transaction details (when and how much) and also my current load balance.

5. She did something on the computer, went to the back office and got a SIM card with adapter.

TM SIM adapter.

6. I let her use my phone for a while to activate the new SIM card. She has her own SIM ejector tool.

Globe SMS re: SIM upgrade.

7. To make sure that the new SIM card is activated, she (mis)called my number again. I didn't get the old SIM card with the same number back. It's of no use anyway.

Now, I can see a 4G sign on the signal status bar on my phone and got 1GB mobile data as a bonus (which I won't be able to consume fully because I usually surf the net thru WiFi). I'm not sure if the upgrade will solve signal problems not just for surfing but also for calls and texts. Still hoping for the best.