LaTex multirow overlaping with next row

I have changed the code in the paragraph title Corrosion and Creep with package makecell which is better than creating tables within the tabular environ -- have look -- also using package booktabs and using toprule, midrule, bottomrule gives better spacing -- you can follow the same for the rest of the table -- will give you the desired result

makecell[l]{1) Surface imperfections caused by corrosion increase drag, reducing the fan efficiency. 2) Reduces structural integrity of the fan blades which increases chances of premature failure.~}

Partial code changed MWE -- remaining left for the OP

documentclass{article}
usepackage{subcaption}
usepackage{booktabs}
usepackage{multirow}
usepackage{makecell}
renewcommandthesubfigure{1alphalph{value{subfigure}}}

begin{document}
    begin{table*}
        centering
        caption{FMEA analysis on the possible failure modes of the fan blade.}
        label{tab:FMEA}
%       resizebox{linewidth}{!}{%
            begin{tabular}{clclcclc} 
                toprule
                Failure Mode               & multicolumn{1}{c}{Effects}                                                                                                                                                                                                                                     & S                  & multicolumn{1}{c}{Causes}                                                                              & P                      & D                     & multicolumn{1}{c}{Design Considerations}                                                                                                & RPN   
                midrule
                multirow{2}{*}{Fatigue}   & multirow{2}{*}{begin{tabular}[c]{@{}l@{}}1) Fan will be inoperable until fan blade replaced.  2) Failure during operation may  lead to injuries or damages to other equipment. end{tabular}}                                                       & multirow{2}{*}{9} & begin{tabular}[c]{@{}l@{}}Alternating load cycles  when RPM is decreased or increasedend{tabular} & 8                      & 6                     & begin{tabular}[c]{@{}l@{}}1)Reduce the frequency of RPM change and reduce deformation during loading. end{tabular}                 & 432  
                &                                                                                                                                                                                                                                                                 &                    & begin{tabular}[c]{@{}l@{}}High temperature induces  propagation of microcracksend{tabular}          & 9                      & 1                     & begin{tabular}[c]{@{}l@{}}2) Operating temperature (400 C) must not be higher than 0.3$T_m$ of  selected material. end{tabular}  & 81    
                midrule
                multirow{2}{*}{Corrosion} & makecell[l]{1) Surface imperfections caused by corrosion increase drag, reducing the fan efficiency. 2) Reduces structural integrity of the fan blades which increases chances of premature failure.~} & multirow{2}{*}{6} & begin{tabular}[c]{@{}l@{}}Abrasion and degradation of anti-corrosion coatingend{tabular}            & 10                     & 2                     & begin{tabular}[c]{@{}l@{}}1) Select a more corrosion-resistant material to reduce reliance on anti-corrosion coatings.end{tabular} & 120  
                &                                                                                                                                                                                                                                                                 &                    & Pitting corrosion                                                                                       & 7                      & 6                     & begin{tabular}[c]{@{}l@{}}2) Avoid passive metals for the construction of the blade.end{tabular}                                     & 252   
                midrule
                multirow{2}{*}{Creep}     & makecell[l]{1) May result in loss of performance if blade is deformed, or injuries if catastrophic failure occurs.  2) More frequent blade replacements would increase operating costs }                & multirow{2}{*}{9} & begin{tabular}[c]{@{}l@{}}Constant loading of the fan bladesend{tabular}                            & 9                      & 4                     & begin{tabular}[c]{@{}l@{}}1) Finite element analysis may help obtain the most optimal blade geometry.end{tabular}                  & 324  
                &                                                                                                                                                                                                                                                                 &                    & begin{tabular}[c]{@{}l@{}}High temperature increases dislocation mobilityend{tabular}               & 9                      & 1                     & begin{tabular}[c]{@{}l@{}}2) The operating temperature (400 C) must not  exceed 0.5$T_m$ of the materialend{tabular}               & 81    
                midrule
                Impact                     & begin{tabular}[c]{@{}l@{}}1) Damage surface and reduceaerodynamic efficiency of the blade.  2) A large object may cause deformation or complete failure of the blade, deeming the machine inoperable. end{tabular}                                  & 9                  & begin{tabular}[c]{@{}l@{}}Ingestion of solid objects into the fan end{tabular}                      & multicolumn{1}{l}{10} & multicolumn{1}{l}{2} & begin{tabular}[c]{@{}l@{}}The blades must be inspected frequently for surface damage or any deformation. end{tabular}              & 180  
                bottomrule
            end{tabular}
%       }
    end{table*}
end{document}