I know that my question could be unclear, but let me firstly explain the issue to give me your advice.
I've built a website using VueJS linked it with PHP API (Redbean ORM) with MySQL DB engine hosted with GoDaddy Economy Shared plan and everything works fine as well.
For the first months of production, it works fine with its data and the client and his visits. But recently, the website is getting slow in responding the requests to server and also for the first load. Sometimes works good but suddenly stops loading and getting (504 Gateway Time-out) HTTP response. Even with some browsers works and some other does not, also with some mobile platforms like iPhone getting slow loading. As you know, VueJS uses SPA to make website super faster than traditional loading navigation.
It's clear that maybe the shared hosting plan is the main reason and we should upgrade to higher business plans to solve it, but I preferred to ask the community here if anyone has any idea to solve this issue.
The website object is online store and gallery for cosmetics and makeups, no payment APIs integrated.
Any ideas may I use to improve stability and responding? Thank you.